Hi,

I've noticed that Gnus (in Emacs 25.3) is not showing couple of messages in my
IMAP folder, which are showing up just fine in other MUA (Thunderbird). The
messages are neither showing up when visiting the folder normally, nor on
search.

Following is what I see in *imap log* buffer, when I try to search for the
messages with subject "help":

--8<---------------cut here---------------start------------->8---
15:29:37 [mail.domain.tld] 367 SELECT "INBOX"^M
15:29:37 [mail.domain.tld] 368 UID SEARCH SUBJECT "help"^M
15:29:37 [mail.domain.tld] 369 SELECT "INBOX"^M
15:29:37 [mail.domain.tld] 370 UID FETCH 12114,12555,15544,15651,66216:66217,91222,91270,103779,105201,117165,122773:122774,123031,123837,127703,129897,133254,134698,134984 (UID RFC822.SIZE BODYSTRUCTURE BODY.PEEK[HEADER.FIELDS (Subject From Date Message-Id References In-Reply-To Xref X-Spam-Status X-Bogosity X-CRM114-Status To Newsgroups Cc)])^M
--8<---------------cut here---------------end--------------->8---

UIDs 135021, and 135051 are not being fetched by the Gnus.

Following is an excerpt from the communication over telnet:

--8<---------------cut here---------------start------------->8---
367 SELECT "INBOX"
* FLAGS (\Answered \Flagged \Deleted \Seen \Draft gnus-expire Junk NonJunk)
* OK [PERMANENTFLAGS (\Answered \Flagged \Deleted \Seen \Draft gnus-expire Junk NonJunk \*)] Flags permitted.
* 6547 EXISTS
* 0 RECENT
* OK [UNSEEN 6547] First unseen.
* OK [UIDVALIDITY 1293092912] UIDs valid
* OK [UIDNEXT 135054] Predicted next UID
* OK [HIGHESTMODSEQ 272541] Highest
367 OK [READ-WRITE] Select completed (0.008 + 0.000 + 0.007 secs).
368 UID SEARCH SUBJECT "help"
* SEARCH 12114 12555 15544 15651 66216 66217 91222 91270 103779 105201 117165 122773 122774 123031 123837 127703 129897 133254 134698 134879 134904 134923 134969 134970 134984 135021 135051
368 OK Search completed (0.050 + 0.000 + 0.049 secs).
369 UID FETCH 135021,135051  (UID BODY.PEEK[HEADER.FIELDS (Date)])
* 6539 FETCH (UID 135021 BODY[HEADER.FIELDS (DATE)] {40}
Date: Fri, 8 Dec 2017 00:13:32 +0530

)
* 6546 FETCH (UID 135051 BODY[HEADER.FIELDS (DATE)] {41}
Date: Fri, 15 Dec 2017 23:41:47 +0530

)
369 OK Fetch completed (0.001 + 0.000 secs).
--8<---------------cut here---------------end--------------->8---

Following is through Dovecot tools, as I happen to administer this mail server:

--8<---------------cut here---------------start------------->8---
λ doveadm search mailbox INBOX subject help |awk '{ print $2; }' |xargs -n 1 -r doveadm fetch 'uid hdr.date' mailbox INBOX uid 
uid: 12114
hdr.date: Sun, 26 Apr 2015 07:05:21 -0700
uid: 12555
hdr.date: Mon, 04 May 2015 18:10:28 -0600
uid: 15544
hdr.date: Fri, 12 Jun 2015 13:14:10 -0400 (EDT)
uid: 15651
hdr.date: Sat, 13 Jun 2015 16:14:44 +0530
uid: 66216
hdr.date: Mon, 09 May 2016 15:23:37 +0530
uid: 66217
hdr.date: Mon, 09 May 2016 15:33:53 +0530
uid: 91222
hdr.date: Tue, 1 Nov 2016 23:41:57 +0530
uid: 91270
hdr.date: Wed, 02 Nov 2016 04:10:05 +0530
uid: 103779
hdr.date: Fri, 20 Jan 2017 22:20:13 +0000
uid: 105201
hdr.date: Mon, 30 Jan 2017 15:39:57 -0500
uid: 117165
hdr.date: Thu, 20 Apr 2017 02:33:10 +0000
uid: 122773
hdr.date: Thu, 1 Jun 2017 13:00:42 +0530
uid: 122774
hdr.date: Thu, 1 Jun 2017 13:00:48 +0530
uid: 123031
hdr.date: Sat, 03 Jun 2017 01:40:48 +0530
uid: 123837
hdr.date: Thu, 8 Jun 2017 13:55:55 +0530
uid: 127703
hdr.date: Thu, 06 Jul 2017 00:27:31 +0000
uid: 129897
hdr.date: Fri, 21 Jul 2017 07:43:35 -0400
uid: 133254
hdr.date: Wed, 16 Aug 2017 13:06:57 -0400
uid: 134698
hdr.date: Sun, 17 Sep 2017 14:09:04 -0400 (EDT)
uid: 134879
hdr.date: Tue, 24 Oct 2017 12:47:52 +0530
uid: 134904
hdr.date: Mon, 30 Oct 2017 16:17:39 +0530
uid: 134923
hdr.date: Tue, 7 Nov 2017 00:30:54 +0530
uid: 134969
hdr.date: Thu, 23 Nov 2017 23:42:24 +0000
uid: 134970
hdr.date: Thu, 23 Nov 2017 23:42:25 +0000
uid: 134984
hdr.date: 28 Nov 2017 12:00:49 -0500
uid: 135021
hdr.date: Fri, 8 Dec 2017 00:13:32 +0530
uid: 135051
hdr.date: Fri, 15 Dec 2017 23:41:47 +0530
--8<---------------cut here---------------end--------------->8---

Any ideas why ? Or how to debug this further ?

Thanks!
-- 
Ashish SHUKLA

“I have  discovered that all human  evil comes from this,  man's being
unable to sit still in a room.”
                                                         (Blaise Pascal)

Sent from my Emacs