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I don't understand this message and don't find anyplace in account settings to rectify it. Help!

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"The POP3 mail server (inbound.att.net) does not support UIDL or XTND XLST, which are required to implement the ``Leave on Server, ``Maximum Message Size or ``Fetch Headers Only options. To download your mail, turn off these options in the Server Settings for your mail server in the Account Settings window."

I can't get incoming mail without going to Yahoo and I wouldn't use T-Bird if I liked Yahoo/AT&T. Thanks.

"The POP3 mail server (inbound.att.net) does not support UIDL or XTND XLST, which are required to implement the ``Leave on Server'', ``Maximum Message Size'' or ``Fetch Headers Only'' options. To download your mail, turn off these options in the Server Settings for your mail server in the Account Settings window." I can't get incoming mail without going to Yahoo and I wouldn't use T-Bird if I liked Yahoo/AT&T. Thanks.

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

Do any of the following work: 1) Go into offline mode and then return to online mode. To go into offline mode: In the bottom Status Bar, far left, there is a 'two blue screen icon'. click on it and it will change to a 'two black screen icon' . This means you are in offline mode. click on the 'two black screen icon' and it will return to a 'two blue screen' icon which is online mode.

2) Exit Thunderbird. Wait a few moments for background processes to complete. Start Thunderbird.


3) I located some info you could read. Note: pop mail accounts do not use OAuth. Suggest you use the links to read full info.

Access AT&T email through an email app using a secure mail key If you prefer to use an email app that isn’t compatible with OAuth, you’ll have to create a special code called a secure mail key. You’ll use this secure mail key instead of your AT&T password when you set up an email app.

Access AT&T email at att.net You can always use your regular password to access your AT&T email at att.net through a Web browser.

Quote: AT&T email app security to update soon. Act now to avoid email hiccups Do you use a desktop program or a mobile app to access and manage your AT&T email? If so, we suggest you use one with Open Authentication (OAuth) technology, which encrypts your username and password. Learn about OAuth and find out if your app uses OAuth.

If your email program or app doesn’t have OAuth technology, it will only be able to access your AT&T email program or app using a 16-character secure mail key. Be sure to use myAT&T to create a secure mail key for each of your AT&T email addresses and subaccounts, so you can continue to:

read section regarding: Create a secure mail key Learn how to create a secure mail key from your mobile device, tablet, or computer. Have your User ID and password ready to sign in to myAT&T.

Toad-Hall modificouno o

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What is "OAuth" -- is this an att thing or an internet standard/specification?

Today got the same error from aol (was Verizon). WHY IS THIS HAPPENING ?? WHAT HAS CHANGED IN SPECS FOR A POP SERVER ??? Does this error message come from Thunderbird or from aol?

ERROR WITH ACCOUNT xxx@verizon.net

The POP3 mail server (pop.aol.com) does not support UIDL or XTND XLST, which are required to implement the ``Leave on Server, ``Maximum Message Size or ``Fetch Headers Only options. To download your mail, turn off these options in the Server Settings for your mail server in the Account Settings window.

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re :Does this error message come from Thunderbird or from aol?

From Yahoo server which has AOL, AT&T, BT and several others using the yahoo servers. This error message only effects those using a Yahoo server and a POP mail account. Recently, several reports have been made on yahoo forums about this error messgae which effects users of Thunderbird, Opera Mail, Seamonkey and Outlook. I'm sure there may be others as well.

If you were cynical, you may think yahoo were being a pain on purpose because they want people to stop using POP and use IMAP instead or access yahoo webmail account via a browser.

As already mentioned, usually this is temporary. Sometimes restarting Thunderbird can fix issue. Sometimes it only seems to occur when 'Get Messages' is used, but all is ok if the auto check looks for mail.

I logged onto webmail and removed a load of really old emails I did not need on server, then emptied Spam and Trash. Then restart Thunderbird and all has been ok since.

Some people have found that using two step verification and creating and using an application specific password (instead of normal pasword) in Thunderbird also resolved this issue. Good info at links previously given.

IMAP mail accounts use OAuth. When creating an imap mail account, you would be prompted to logon to yahoo/webmail using normal password to verify it is you trying to access server, then yahoo generate OAuth password key which is stored in same place as normal password in Thunderbird. When imap account accesses server, it uses that generated key and not your normal password.

Gmail also use OAuth technology. Both Gmail and Yahoo claim it makes things more secure. You can make your own mind up on that. It is worth remembering that they are now generating the passwords. Good info explaining alot at these links.


This link seems to underpin the thoughts that yahoo are trying to force people to use what they want them to use and not what their clients want to use:

This link also makes interesting reading. Note they mention 'Oath' which is a bit different from 'OAuth'. https://www.theverge.com/2018/4/14/17237864/oath-aol-yahoo-email-privacy-terms-scan-ads https://en.wikipedia.org/wiki/Oath_Inc.

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Maybe its generated when you have too many saved emails in their server. I emptied it, and now the error msg seems to have gone away.

Its useful to have them on the server -- when your primary computer goes down, you can re-load them into a backup computer.

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Its time for Proton Mail, but its an impossible job to change my email address already embedded in contact & security check emails for forums, websites, blogs... let alone a LIFETIME of correspondants.

>policy also states that the company can “analyze your content and other information (including emails, instant messages, posts photos, attachments, and other communications),”

and it singles out messaging from financial institutions, saying that it “may analyze user content around certain interactions with financial institutions.”

Oath says that its automated systems will strip out “information that on its own could reasonably identify the recipient.”

EXCEPT THAT IT IS PROVEN THAT AGGREGATE INFORMATION CAN FAIRLY EASILY IDENTIFY YOU PERSONALLY

It might also collect Exchangeable Image File Format (EXIF) data from images that you upload, and utilize image recognition to “identify and tag scenes, color, best crop coordinates, text, actions, objects, or public figures.”