For the past two weeks or so one of our customers (with a dedicated server) has been having trouble either sending emails or receiving emails (or both!). The customer in question uses Microsoft [DELETED-Lookout-DELETED] Outlook (of course—sigh) so Smirk has been looking into the issue and couldn't for the life of him get Outlook to work.
Thunderbird? [1]
Yes.
Webmail?
Yes.
Outlook?
Outlook not so good [2].
He spent so much time he decided to reinstall the server (there are some other issues with the server—namely centered around the control panel Ravencore [3]) and start over with a fresh slate.
I had just finished installing a new server when P asked if this was the customer that had the security audit [4].
Oh.
Um.
It is. [5]
XXXX!
I then talked with Smirk to get an exact clarification of the problem and it's a problem with one (1) email account. Just one. Everything else works fine. So Smirk left it up to me—if I could fix the original server, fine. Or if I could get the new server working, fine. Just get it working.
I did some tests on the original server and checked the logs.
>
```
Sep 12 16:31:23 XXXXXXXXX dovecot: POP3(XXXXXXXXXXXXXXXXX): pop3_uidl_format setting is missing from config file
```
pop3_uidl_format? What's that all about?
>
```
# POP3 UIDL format to use. You can use following variables:
#
# %v - Mailbox UIDVALIDITY
# %u - Mail UID
# %m - MD5 sum of the mailbox headers in hex (mbox only)
# %f - filename (maildir only)
#
# If you want UIDL compatibility with other POP3 servers, use:
# UW's ipop3d : %08Xv%08Xu
# Courier version 0 : %f
# Courier version 1 : %u
# Courier version 2 : %v-%u
# Cyrus (<= 2.1.3) : %u
# Cyrus (>= 2.1.4) : %v.%u
# Older Dovecots : %v.%u
#
# Note that Outlook 2003 seems to have problems with %v.%u format which was
# Dovecot's default, so if you're building a new server it would be a good
# idea to change this. %08Xu%08Xv should be pretty fail-safe.
#
# NOTE: Nowadays this is required to be set explicitly, since the old
# default was bad but it couldn't be changed without breaking existing
# installations. %08Xu%08Xv will be the new default, so use it for new
# installations.
#
#pop3_uidl_format =
```
Outlook.
Why'd it have to be [DELETED-snakes-DELETED] Outlook?
Needless to say, it worked after making the required configuration change (and then it was getting it so that the control panel wouldn't wipe out said configuration change)