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[UNAVAILABLE] UID FETCH Server error while fetching messages from Yahoo

  • 9 replies
  • 1 has this problem
  • 16 views
  • Last reply by rdiez

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I have been using Yahoo for years. Many months ago I successfully upgraded to OAuth2, when Yahoo changed its servers, and carried on using Yahoo without problems.

But around 2 days ago, I started having this problem:

[UNAVAILABLE] UID FETCH Server error while fetching messages

This happens when I open an e-mail in order to read it. Many other operations continue to work, like downloading the e-mail headers, deleting e-mails, marking them as read. Only downloading e-mails (for reading them) or moving them fails.

There is no obvious error cause in the IMAP log.

I am using the Thunderbird 91.5.0 that comes with Ubuntu 20.04.3. I have 2 such PCs and both fail in the same way.

Other e-mail accounts in the same Thunderbird still work fine.

The first thing I wanted to ask is whether somebody else is having this problem.

I have been using Yahoo for years. Many months ago I successfully upgraded to OAuth2, when Yahoo changed its servers, and carried on using Yahoo without problems. But around 2 days ago, I started having this problem: [UNAVAILABLE] UID FETCH Server error while fetching messages This happens when I open an e-mail in order to read it. Many other operations continue to work, like downloading the e-mail headers, deleting e-mails, marking them as read. Only downloading e-mails (for reading them) or moving them fails. There is no obvious error cause in the IMAP log. I am using the Thunderbird 91.5.0 that comes with Ubuntu 20.04.3. I have 2 such PCs and both fail in the same way. Other e-mail accounts in the same Thunderbird still work fine. The first thing I wanted to ask is whether somebody else is having this problem.

All Replies (9)

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If you are not using an APP password, that may be the problem. They are created from the Yahoo website for use in email clients, such as TB.

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If that were an authentication problem, I couldn't see the new e-mail headers, mark them as read or delete them.

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A similar error has been seen in the past, but mainly for Yahoo POP accounts.

http://kb.mozillazine.org/Yahoo#The_POP3_email_server_.28plus.pop.mail.yahoo.com.29_does_not_support_UIDL_or_XTND_or_XLST

The error has occurred in IMAP accounts, and might be fixed by emptying Trash:

http://forums.mozillazine.org/viewtopic.php?p=14769783#p14769783

If the authentication on the incoming and outgoing servers is OAuth2, as it should be for Yahoo, an app password is not required. The account password is entered during OAuth2 authentication and a token is stored in Saved Passwords.

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Thanks for the links. I tried everything, emptying the trash and other folders and other e-mails, to no avail. It's really annoying.

I just created a new Thunderbird profile, and connected to the same Yahoo account from scratch, and I get the same errors.

I hope it is a bug in the Yahoo servers, and they fix it soon. Unfortunately, Yahoo does not have any way to report such problems, as far as I can tell.

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Would you mind posting your settings? I just set up a Yahoo account with APP and it's working fine.

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What is "APP"?

I just used the defaults. Thunderbird autodetects everything correctly, as far as I can tell:

imap.mail.yahoo.com, 993 SSL/TLS OAuth2

Maybe it is because I am in Germany. I am using a @yahoo.de e-mail address. The IMAP server is (as seen from here):

$ ping imap.mail.yahoo.com PING internal.imap.mail.g03.yahoodns.net (77.238.185.51) 56(84) bytes of data. 64 bytes from sky700-2.mail.vip.ir2.yahoo.com (77.238.185.51): icmp_seq=1 ttl=54 time=42.6 ms

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I don't know all Yahoo features and defer to Sfhowes on the differences. All I can share is that mine works. You need to log into Yahoo and create an APP password. This is a one-time creation that is used to replace your TB password. Your web password remains unchanged. I don't know if that fixes your problem, but I'm using same server setup.

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Wait, everything started working again. Just now! Both in the new and in the old Thunderbird profiles.

I guess that Yahoo has finally woken up. It only took 3 days this time. 8-)

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I didn't use an APP password, I am using OAuth2, both in the old and in the just-created Thunderbird profile for test purposes. My guess is that Yahoo screwed up. It wouldn't be the first time.