Judge POOLER dissents in a separate opinion.
JOHN M. WALKER, JR., Chief Judge.
Defendant-appellant Joseph Martin appeals from the March 19, 2004, amended judgment of the United States District Court for the Eastern District of New York (Leonard D. Wexler, Judge), convicting him, after his guilty plea, of possession of child pornography in violation of 18 U.S.C. § 2252A(a)(5)(B), and sentencing him principally to a term of imprisonment of twenty-seven months. On this appeal, Martin challenges the district court’s May 15, 2003, memorandum and order denying his motion to suppress evidence seized from his home pursuant to a search warrant.
The search arose out of “Operation Can-dyman,” an extensive government investigation of persons suspected of collecting and distributing child pornography over the internet. Most of the searches conducted in Operation Candyman were pursuant to warrants supported by affidavits, each of which recounted the same investigative findings by the same FBI agent but contained additional facts specific to the particular search. Subsequent to the issuance of the warrant in this case, the supporting affidavit was determined to contain misstatements about general investigative facts. Like many defendants in these Candyman cases, Martin moved to suppress the fruits of the search. Because the affidavit, even without these false statements, supports a finding of probable cause, we affirm the district court’s denial of the suppression motion.
Martin, however, was sentenced under the mandatory Guidelines regime existing [70]*70prior to United States v. Booker, 543 U.S. -, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005). We, therefore, remand the case to the district court for further proceedings consistent with Booker and United States v. Crosby, 397 F.3d 103 (2d Cir.2005).
BACKGROUND
I. The Supporting Affidavit
The Martin affidavit covered the search of different premises and contained facts pertaining to three separate child-pornography e-groups:1 “Candyman,” as well as “girlsl2-16” and “shangrLia.” The portions relevant to Martin’s home, and this appeal, alleged that an individual residing there was only a member of girlsl2-16. But the affidavit incorporated the following description of the Candyman e-group and its features into its general discussion of the girlsl2-16 e-group.
A. Operation Candyman
In January 2001, FBI Special Agent Geoffrey S. Binney joined the Candyman e-group in an undercover capacity. The Candyman webpage announced the following to anyone considering joining:
This group is for People who love kids. You can post any type of messages you like too [sic] or any type of pics or vids you like too [sic], P.S. IF WE ALL WORK TOGETHER WE WILL HAVE THE BEST GROUP ON THE NET.
In order to use the full website, an individual was required to become a member of the e-group.
Special Agent Binney’s affidavit went on to assert that members had access to a number of features on the website: (1) a “Files” section allowed users to post images and video clips for other members to access and download; (2) a “Polls” section “allowed Candyman E-group members to answer survey questions, such as ‘what age group do you prefer?’ (3) a “Links” section permitted members “to post URLs for other web sites containing similar content”; (4) a “Chat” section enabled members “to engage in real time chat conversations with each other”; (5) an e-mail list, to which all new members were automatically2 added, circulated messages and files when they were sent to the e-group; and (6) a “Messages” area stored all the messages and files transmitted to the group so that members could review' them later. See generally United States v. Froman, 355 F.3d 882, 884-85 (5th Cir.2004) (describing features of Candyman website).
In the “Files” section, Special Agent Binney found and downloaded approximately 100 pictures and movies of child pornography and so-called child erotica. From January 2, 2001, when Binney joined the Candyman e-group, until February 6, 2001, when the e-group was shut down, he received nearly 500 e-mails, to which were attached roughly 300 files containing child pornography or child erotica.
After the warrant authorizing the search of Martin’s home was issued, misstatements were discovered in the standard provisions of the affidavit. The affidavit declared that every new member was automatically added to an e-mail list and thereafter “automatically received every e-mail message and other file transmitted to the Candyman E-group by any Candyman E-group member.” It was later revealed that this statement was not universally [71]*71true. Those who registered by e-mail were automatically added to the e-mail list, but those who registered on the Candyman website could opt out of this feature.
B. Girlsl2-16 E-group
During the course of the Candyman investigation, the FBI also observed that some Candyman members had begun to exchange information about two new e-groups: “girlsl2-16” and “shangrLia,” both of which also focused on child pornography. The girlsl2-16 e-group — central to Martin’s appeal — included the following welcome message:
Hi all, This group is for all those ho [sic] appreciate the young female in here [sic] finest form. Watching her develop and grow is like poetry in motion [sic], to an age where she takes an interest in the joys and pleasures of sex. There is probably nothing more stimulating than watching a young teen girl discover the pleasures of the orgasm. The joy of feeling like she is actually coming into womanhood. It’s an age where they have no preconditions about anything, just pure opennes [sic]. What a joy to be a part of that wonderful experience and to watch the development of this perfect form. This is the place to be if you love 11 to 16 yr olds. You can share experiences with others, share your views and opinions quite freely without censorship. You can share all kinds of other information as well regarding— your current model: if you are a photographer. Where the best place to meet gitls [sic] is. The difficulties you experience in your quest. The best way to chat up. Good places to pick girls up. Girls you would like to share with others. The choice is all yours. Welcome home! Post videos and photographs ... and how about your true life experiences with them so that other viewers can paint a mental picture andin [sic] some ways share the experience with you. You could connect with others from the same country as you and get together sociall [sic] if you wish. The choice is all yours. How about a model resource for photographers? It’s all up to you and is only limited by your own imaginations. Membership is open to anyone, but you will need to post something. Mybe [sic] a little bit about yourself/what your interests are (specifically), your age, location ... and a pic or vid would be a good to [sic]. By doing this other members (or potential members) with the same interest may then contact you if you wish them to.
The shangri_la e-group welcome message simply announced, “Hardcore Only.” These two e-groups had “many of the same features as the Candyman E-group,”3 and they also offered membership lists setting forth each member’s Yahoo! user identification, his truncated e-mail address, and the date each member joined the group.
The girlsl2-16 membership list included a member whose email address (Joeym@optonline.net) was ultimately found to be associated with an individual living at Martin’s house. The affidavit did not allege that Joeym@optonline.net was additionally a member of the Candyman, but, as noted, the discussion of girlsl2-16 depended upon the description of the Can-dyman’s features.
[72]*72Between February 2, 2001, and February 15, 2001, while Special Agent Binney was an undercover member of girlsl2-16, he received 193 e-mails, of which fourteen contained pictures of child pornography and seventy-seven contained images of child erotica.
C. Child-Pornography Collector Computer Use and Characteristics
The affidavit also included an extensive discussion, based on the experiences of Special Agent Binney, of the way individuals who collect and produce child pornography use computers and the internet to access, acquire, and disseminate this material. It further detailed the characteristics of child-pornography collectors, drawn from the extensive experience of a special agent in the FBI’s Behavioral Analysis Unit. This section emphasized that collectors tend to maintain their illicit collections and that they rarely, if ever, destroy them.
II. Procedural History
On the basis of the affidavit, the magistrate judge issued a warrant authorizing the search of, inter alia, Martin’s residence. The FBI executed the warrant and seized Martin’s computer, on which hundreds of images and video clips of child pornography and child erotica were found.
Martin’s indictment for violation of the federal child-pornography laws was handed up in June 2002 and unsealed a month later. In August and then in December 2002, the government wrote two letters to Martin that revealed the affidavit’s misstatements about automatic e-mail delivery. As a result of the disclosure of the false statements in a separate case, United States v. Strauser, 247 F.Supp.2d 1135 (E.D.Mo.2003), the government informed Martin that Special Agent Binney testified at a hearing pursuant to Franks v. Delaware, 438 U.S. 154, 98 S.Ct. 2674, 57 L.Ed.2d 667 (1978), that he received emails automatically because he subscribed to the Candyman e-group by e-mail and not through the website. But an official from Yahoo!, which owned and operated the e-group service on which the Candy-man operated, testified that company records indicated that Binney subscribed through the group’s website and, therefore, should have known that e-mail receipt was optional.
On the basis of these disclosures, Martin moved to suppress all evidence seized from his residence and for a Franks hearing. Relying on his previous Candyman decision in United States v. Coreas, 259 F.Supp.2d 218 (E.D.N.Y.2003), Judge Wexler denied Martin’s motion on May 12, 2003, stating:
Here, as in Coreas, the facts presented, even without the false statement, support such a finding [of probable cause]. First, the affidavit contains extensive background information regarding subscribers to groups such as the Candy-man group and the proclivity of members to use such groups to collect, trade and retain images of child pornography. The affidavit further describes the Can-dyman group in detail. With the exception of the false statement regarding automatic e-mail receipt, all statements regarding the group and the agent’s receipt of numerous images of child pornography are truthful. It is also without question that the Defendant joined the group. These facts are sufficient to establish probable cause to believe that a search of Defendant’s computer would reveal evidence of criminal activity. Accord United States v. Copian, No. CR 02-319(ARR) (E.D.N.Y. August 15, 2002) (holding that affidavit in Candy-man investigation was sufficient to establish probable cause even without the statement regarding receipt of e-mail).
[73]*73United States v. Martin, No. CR 02-730, slip op. at 2-3 (E.D.N.Y. Mar. 12, 2003).4
On September 16, 2003, Martin pleaded guilty while reserving his right to appeal the district court’s suppression ruling. This appeal followed.
DISCUSSION
I. The Suppression Motion
Martin contends that, after excising the false statements, the affidavit is insufficient to make out a showing of probable cause. He argues that the district court erroneously determined that his membership in the girlsl2-16 e-group demonstrated probable cause, and that the district court’s finding was simply premised on guilt by association. He also requests a Franks hearing to determine whether the false statements were made intentionally or recklessly. We agree with the government that, even without the false statements, the affidavit established probable cause.
A. Applicable Law
The Fourth Amendment prohibits “unreasonable searches and seizures,” and the Warrants Clause mandates that “no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.” U.S. Const. amend. IV. “There is ... a presumption of validity with respect to the affidavit supporting [a] search warrant.” Franks, 438 U.S. at 171, 98 S.Ct. 2674. “In certain circumstances, however, a defendant may challenge the truthfulness of factual statements made in the affidavit, and thereby undermine the validity of the warrant and the resulting search or seizure.” United States v. Awadallah, 349 F.3d 42, 64 (2d Cir.2003). “However, every statement in a warrant affidavit does not have to be true.” United States v. Canfield, 212 F.3d 713, 718 (2d Cir.2000) , (internal quotation marks omitted).
In Franks v. Delaware, the Supreme Court held that a defendant may challenge the validity of a search warrant alleged to contain deliberately or recklessly false or misleading information. 438 U.S. at 164-72, 98 S.Ct. 2674. To void the warrant and suppress the evidence, a defendant must demonstrate, by a preponderance of the evidence, that (1) the affidavit contained “a false statement knowingly and intentionally, or with reckless disregard for the truth,” and (2) “the allegedly false statement is necessary to the finding of probable cause.” Id. at 156, 98 S.Ct. 2674; accord Canfield, 212 F.3d at 717-18.
A false statement “is material when ‘the alleged falsehoods or omissions were necessary to the [issuing] judge’s probable cause finding.’ ” Awadallah, 349 F.3d at 64-65 (quoting Canfield, 212 F.3d at 718). We have explained that we “gauge [the] materiality [of the misstatements] by a process of subtraction.” Id. at 65.
To determine if the false information was necessary to the issuing judge’s probable cause determination, i.e., material, “a court should disregard the allegedly false statements and determine whether the remaining portions of the affidavit would support probable cause to issue the warrant.” If the corrected affidavit supports probable cause, the inaccuracies were not material to the [74]*74probable cause determination and suppression is inappropriate.
Canfield, 212 F.3d at 718 (quoting United States v. Trzaska, 111 F.3d 1019, 1027-28 (2d Cir.1997)). Thus, “[t]he ultimate inquiry is whether, after putting aside erroneous information and material omissions, ‘there remains a residue of independent and lawful information sufficient to support probable cause.’ ” Id. (quoting United States v. Ferguson, 758 F.2d 843, 848 (2d Cir.1985)); accord Awadallah, 349 F.3d at 65; Trzaska, 111 F.3d at 1027-28.
A judge’s probable-cause determination is not overly strict. Presented with a warrant application, the judge must “simply ... make a practical, common-sense decision whether, given all the circumstances set forth in the affidavit before him, including the ‘veracity’ and ‘basis of knowledge’ of persons supplying hearsay information, there is a fair probability that contraband or evidence of a crime will be found in a particular place.” Illinois v. Gates, 462 U.S. 213, 238, 103 S.Ct. 2317, 76 L.Ed.2d 527 (1983) (emphasis added). “[Pjrobable cause is a fluid concept — turning on the assessment of probabilities in particular factual contexts — not readily, or even usefully, reduced to a neat set of legal rules.” Id. at 232, 103 S.Ct. 2317. The Supreme Court has held that probable cause does not require a “prima facie showing”:
Finely tuned standards such as proof beyond a reasonable doubt or by a preponderance of the evidence, useful in formal trials, have no place in the magistrate’s decision. While an effort to fix some general, numerically precise degree of certainty corresponding to “probable cause” may not be helpful, it is clear that “only the probability, and not a prima facie showing, of criminal activity is the standard of probable cause.”
Id. at 235, 103 S.Ct. 2317 (quoting Spinelli v. United States, 393 U.S. 410, 419, 89 S.Ct. 584, 21 L.Ed.2d 637 (1969)).
“ ‘Whether the untainted portions [of the affidavit] suffice to support a probable cause finding is a legal question, and we review the district court’s ruling on that question de novo.’ ” Canfield, 212 F.3d at 717 (quoting United States v. Nanni, 59 F.3d 1425, 1433 (2d Cir.1995)); see also United States v. Smith, 9 F.3d 1007, 1011 (2d Cir.1993).
B. The “Corrected” Affidavit Supports Probable Cause
We conclude that the affidavit, after being corrected for the error, still supports a probable-cause finding and that Judge Wexler did not err in denying the suppression motion.5 As such, we need not reach the question of whether the misstatements were made knowingly or recklessly. See Franks, 438 U.S. at 156, 98 S.Ct. 2674.
The corrected affidavit provided the magistrate judge with facts sufficient for her to conclude that the overriding, if not the sole, purpose of the girlsl2-16 e-group was illicit (to facilitate the receipt and distribution of child pornography); that an email address of a girlsl2-16 member was linked to Martin’s house; that collectors of child pornography overwhelmingly use the internet and computers to distribute and hoard this illegal pornographic material; and that, accordingly, there was a “fair probability,” given the totality of the circumstances and common sense, Gates, 462 [75]*75U.S. at 238, 103 S.Ct. 2317, that evidence of a crime would be found at Martin’s home because membership in the e-group reasonably implied use of the website.
First, the girlsl2-16’s welcome message unabashedly announced that its essential purpose was to trade child pornography. All members were greeted with the explicit introduction that “[t]his group is for all those ho [sic] appreciate the young female in here [sic] finest form. Watching her develop and grow is like poetry in motion [sic], to an age where she takes an interest in the joys and pleasures of sex.” It invited members to share information about their current “model” for photographers, where to meet girls, the best way to “chat them up,” and “[g]irls you would like to share with others.” And it made clear that members could “[p]ost videos and photographs” of girls. See United States v. Shields, No. 4:CR-01-0384, 2004 WL 832937, at *7 (M.D.Pa. Apr. 14, 2004) (“[T]he purpose of the ‘Candyman’ and ‘Girls 12-16’ websites clearly was to share child pornography.”); United States v. Coplan, No. CR 02-319 (E.D.N.Y. Aug. 15, 2002) (oral decision) (same). The title of the e-group, “girls12-16,” further made plain that the site’s focus was on minor girls.
Second, the affidavit contained an extensive background discussion of the modus operandi of those who use computers for collecting and distributing child pornography, including their reliance on e-groups, e-mail, bulletin boards, file transfers, and online storage. See United States v. Bailey, 272 F.Supp.2d 822, 838 (D.Neb.2003). Third, it described the characteristics and proclivities of child-pornography collectors, specifically how they tend to collect such material, store it, and rarely destroy or discard it. See id.; see also United States v. Harvey, 2 F.3d 1318, 1322-23 (3d Cir.1993) (gathering cases that state collectors of child pornography rarely discard their collections). Fourth, girls12-16’s illicit purpose could be inferred from the website’s technological features (files, messages, polls, e-mail, links, polls, chat, and membership lists) that facilitated the trading of child pornography. See Froman, 355 F.3d at 890 & n. 5. Fifth, the agent confirmed that the material uploaded and downloaded on the girls12-16 site included child pornography and child erotica, and that this material was available to all members. See Shields, 2004 WL 832937, at *7. Sixth, the affidavit established a nexus between the member and the website: The girls12-16 member who utilized the e-mail address Joeym@optonline.net lived at the searched house. See Bailey, 272 F.Supp.2d at 838. Seventh, Joeym@op-tonline.net joined girlsl2-16 voluntarily and never cancelled his membership. See Froman, 355 F.3d at 890-91.
Based on the foregoing, we have no difficulty concluding that the corrected affidavit established probable cause. The affidavit included evidence that an occupant of Martin’s house, Joeym@optonline.net, was a member of the girls12-16 e-group, whose raison d’etre, or primary reason for existence, was the trading and collection of child pornography — a wholly illegal endeavor. It is common sense that an individual who joins such a site would more than likely download and possess such material. See id. (finding it to be “common sense” that one who “voluntarily joins” a child-pornography group and “remains a member of the group ... without cancelling his subscription ... would download such pornography from the website and have it in his possession”); Bailey, 272 F.Supp.2d at 824-25 (“[K]nowingly becoming a computer subscriber to a specialized internet site that frequently, obviously, unquestionably and sometimes automatically distributes electronic images of child pornography to other computer [76]*76subscribers alone establishes probable cause for a search of the target subscriber’s computer.”); see also United States v. Coye, No. 02-CR-732, 2004 WL 1743945, at *3 (E.D.N.Y. Aug. 4, 2004). And this conclusion is supported by the majority of courts that have found that corrected Candyman affidavits set forth probable cause. See, e.g., Schmidt, 373 F.3d at 103-04; Froman, 355 F.3d at 890-91; Coye, 2004 WL 1743945, at *3; Shields, 2004 WL 832937, at *7— *8; Bailey, 272 F.Supp.2d at 824-25, 838-39; Coreas, 259 F.Supp.2d at 220-21; Coplan, No. CR 02-319.
We believe that our conclusion adequately balances the need for law enforcement to have a certain amount of latitude in conducting criminal investigations with the constitutional guarantees of free association and protection against unlawful searches. It does not grant the government an unchecked license to search citizens’ homes simply because they are members of an offensive or disreputable group. Rather, it recognizes that, depending on the totality of the evidence proffered in the affidavit, a substantial likelihood of criminal activity may exist if an individual is a member of an internet e-group whose purpose is unlawful. A contrary conclusion would unnecessarily hamper government investigations by fostering too restrictive a view of probable cause, and would conflict with the pragmatic, common-sense probable-cause analysis that the Supreme Court requires. See Gates, 462 U.S. at 238, 103 S.Ct. 2317.
Ignoring the specific details of the affidavit and its fair inferences, Martin argues that the district court “merely speculated]” that child pornography was being delivered and that probable cause is lacking because the corrected affidavit does not specify that he downloaded this illegal material. While the affidavit does not explicitly state that Martin accessed child pornography, it ties the girlsl2-16 website to an individual living in Martin’s home, and states child pornography was available to all who joined and was being distributed to some of the group’s members, as shown by the agent’s receipt of e-mails containing illegal child pornography and his downloading other such material from the website.
The defect in Martin’s argument is that he conflates evidence of probable cause to sustain a warrant with proof of a prima facie case. As noted earlier, probable cause does not require a prima facie showing that Martin possessed child pornography, in violation of 18 U.S.C. § 2252A(a)(5)(B). See Gates, 462 U.S. at 235, 103 S.Ct. 2317. Rather, because probable cause is a “common-sense” test, the corrected affidavit need only establish that there is a “fair probability that contraband or evidence of a crime will be found in a particular place.” Id. at 238, 103 S.Ct. 2317 (emphasis added). The inquiry turns on an “assessment of probabilities” and inferences, not on proof of specific criminal conduct beyond a reasonable doubt or even by a preponderance of the evidence. Id. at 235, 103 S.Ct. 2317. Simply put, probable cause is a “relaxed standard,” United States v. Leon, 468 U.S. 897, 958, 104 S.Ct. 3405, 82 L.Ed.2d 677 (1984), not a legal determination of guilt or liability, see Gerstein v. Pugh, 420 U.S. 103, 121, 95 S.Ct. 854, 43 L.Ed.2d 54 (1975) (noting “lesser consequences of probable cause determination”); Brinegar v. United States, 338 U.S. 160, 175-76, 69 S.Ct. 1302, 93 L.Ed. 1879 (1949) (indicating that probable cause requires “less than evidence which would justify ... conviction,” but “more than bare suspicion” (internal quotation marks omitted)). The redacted affidavit in this case plainly meets this common-sense threshold.6
[77]*77Although Martin contends that there were legal, as well as illegal, uses for the site, he offers no evidence to support that claim. Martin does not argue, for example, that he, or anyone else, used the e-group as a forum for debating the legalization of child pornography, or simply discussing child pornography or pedophilia. Cf. United States v. Fama, 758 F.2d 834, 838 (2d Cir.1985) (“The fact that an innocent explanation may be consistent with the facts alleged, however, does not negate probable cause.”). Instead, he maintains that “viewing” child pornography on the internet is legal, but this is an open question. See, e.g., United States v. Tucker, 305 F.3d 1193, 1205 (10th Cir.2002) (finding defendant knowingly possessed child pornography, where it was saved in his computer’s cache); United States v. Perez, 247 F.Supp.2d 459, 484 n. 12 (S.D.N.Y. 2003) (noting that question of whether 18 U.S.C. § 2252A(a)(5)(B) reaches “mere internet ‘browsing’ is something of an open question”). See generally Ty E. Howard, Don’t Cache Out Your Case: Prosecuting Child Pornography Possession Laws Based on Images Located in Temporary Internet Files, 19 Berkeley Tech. L.J. 1227 (2004). There is no need to decide this question, however. Even if viewing were legal, that would not defeat probable cause because it is common sense that, in the context of this website and the corrected affidavit, those who view are likely to download and store child pornography. The concern that a person who innocently joins an organization with a mixed purpose might be subjected to an unnecessary and unconstitutional search is not present here because the girls12-16 e-group and its technological features served primarily as a means for effecting illegal activity. At its core, the modus operandi of the girlsl2-16 website was criminal, and that is determinative in this case.
Accordingly, we affirm the district court’s denial of Martin’s suppression motion.
II. Crosby Remand
Following oral argument, the Supreme Court issued its decision in United States v. Booker. In Booker, the Court concluded that a district judge violates the Sixth Amendment when it finds facts and mandatorily uses them to enhance a sentence above the Guidelines range that would have been applicable based solely on facts that the jury found or that the defendant admitted. 543 U.S.-, 125 S.Ct. at 750, 755-56. To remedy this problem, the Court severed the statutory provision that made the Guidelines mandatory, thus rendering the Guidelines “effectively advisory.” Id., 543 U.S.-, 125 S.Ct. at 757.
In United States v. Crosby, we established the procedure this circuit would generally follow in cases where the district court erred in applying the Guidelines mandatorily, but where this procedural error was unpreserved by proper objection below. 397 F.3d at 117-18. “[W]e ruled in Crosby that we would normally remand for determination by the sentencing judge of whether a materially different sentence would have been imposed,” had the judge known at that time that the Guidelines were advisory. United States v. Williams, 399 F.3d 450, 460 (2d Cir.2005).
[78]*78Martin requests a Crosby remand, and the government consents to this relief. Because the district court committed procedural error by sentencing Martin under the mandatory regime, this case is remanded to the district court for further proceedings consistent with Booker and Crosby.
Any appeal taken from the district court’s decision on remand can be initiated only by filing a new notice of appeal. See Fed. R.App. P. 3, 4(b). A party will not waive or forfeit any appropriate argument on remand or on any appeal post-remand by not filing a petition for rehearing of this remand order.
CONCLUSION
For the foregoing reasons, the judgment of the district court is AFFIRMED and the case is REMANDED pursuant to Crosby for consideration of whether to re-sentence.