based only on what I have read their rather strange configuration is

Connection security SSL/TLS Authentication Method Normal Password and the ports they give for TLS.

Matt, Thanks for responding. The problem seems to be in Thunderbird now, as the error message comes from Thunderbird. Here is the AOL grid:

IMAP Incoming mail server (IMAP): imap.aol.com Outgoing mail server (SMTP): smtp.aol.com

Make sure SSL encryption is enabled for the incoming and outgoing mail server. IMAP - 993 - SSL

SMTP - 465 - SSL SMTP - 587 - SSL / TLS

There is no TLS except in the outgoing SMTP which I have kept at 587 and is still working. It is the IMAP which is no longer working. I changed it from 143, which they no longer seem to support, to 993 and have not been able to connect to the IMAP server. That is the server my Gmail accounts use as well. I don't understand Thunderbird's error message or the option they suggest using in advanced settings. Thanks!

with the setting set to port 993 and SSL/TLS connection security.

Open the error console. (Ctrl+Shift+J) Clear it. try to get mail.

Is there an error appear about the SSL or TLS being an obsolete version?

The test I just did on that server was not pretty. https://www.htbridge.com/ssl/?id=vSfbC011

Hi Matt, I tried your suggestion but got the same error message from Thunderbird. I was trying to see whether there was anything on the web and came across an interchange going back 7 years with this same error message occurring https://bugzilla.mozilla.org/show_bug.cgi?id=561055

I tried decreasing the connections to 1 in the advanced IMAP settings as suggested by someone but it didn't help. Unlike some of the instances discussed in that thread, it worked fine after the recent update until I had to make this change. I didn't understand a lot of what was said in that thread, way above my head but it doesn't in any case seem to be a new problem. I don't know what to do... as I really don't want to have to AOL's app. I like all my mail in one place as I have gmail accounts too and I like Thunderbird.

Other thoughts?! Thanks again!

Does an error appear in the error console? That is what I want to know. If it does what does it say.

I think AOL have their collective head lodged out of the sun, but without answers from you I can do no more than guess.

Here are the error console messages since I cleared it a bit ago: Use of Mutation Events is deprecated. Use MutationObserver instead. calendar-widgets.xml:506:18 downloadable font: kern: Too large subtable, table discarded (font-family: "Open Sans" style:normal weight:normal stretch:normal src index:1) source: https://mozorg.cdn.mozilla.net/media/fonts/OpenSans-Regular-webfont.woff common-min.fd3a7ecc03f8.css:1:8069 downloadable font: kern: Too large subtable, table discarded (font-family: "Open Sans" style:normal weight:600 stretch:normal src index:1) source: https://mozorg.cdn.mozilla.net/media/fonts/OpenSans-Semibold-webfont.woff common-min.fd3a7ecc03f8.css:1:8573 downloadable font: kern: Too large subtable, table discarded (font-family: "Open Sans" style:normal weight:bold stretch:normal src index:1) source: https://mozorg.cdn.mozilla.net/media/fonts/OpenSans-Bold-webfont.woff common-min.fd3a7ecc03f8.css:1:9098 downloadable font: kern: Too large subtable, table discarded (font-family: "Open Sans Light" style:normal weight:normal stretch:normal src index:1) source: https://mozorg.cdn.mozilla.net/media/fonts/OpenSans-Light-webfont.woff common-min.fd3a7ecc03f8.css:1:9604 JQMIGRATE: Logging is active common-min.3b0e8abfcc44.js:6:5685 Use of getPreventDefault() is deprecated. Use defaultPrevented instead. common-min.3b0e8abfcc44.js:4:25928 uncaught exception: 2147746065 autosync.js:210:13 uncaught exception: 2147746065 autosync.js:210:13 Webconsole context has changed

None of that makes any sense to me.

It is the IMAP which is no longer working. I changed it from 143, which they no longer seem to support, to 993 and have not been able to connect to the IMAP server.

Please post your Troubleshooting Information. At the top right of the Thunderbird window, click the menu button , then select Help > Troubleshooting Information. Press the "Copy text to clipboard button" and paste the information into your reply.

Here it is:

 Application Basics

   Name: Thunderbird
   Version: 52.3.0
   User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0
   Profile Folder: Open Folder

             (Local drive)
   Application Build ID: 20170815040357
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory
   Profiles: about:profiles

 Mail and News Accounts
   account1:
     INCOMING: account1, , (pop3) pop.verizon.net:995, SSL, passwordCleartext
     OUTGOING: , smtp.verizon.net:465, SSL, passwordCleartext, true

   account2:
     INCOMING: account2, , (none) Local Folders, plain, passwordCleartext

   account3:
     INCOMING: account3, , (pop3) pop.verizon.net:995, SSL, passwordCleartext
     OUTGOING: , smtp.verizon.net:465, SSL, passwordCleartext, true

   account4:
     INCOMING: account4, , (pop3) pop.verizon.net:995, SSL, passwordCleartext
     OUTGOING: , smtp.verizon.net:465, SSL, passwordCleartext, true

   account5:
     INCOMING: account5, , (imap) imap.gmail.com:993, SSL, OAuth2
     OUTGOING: , smtp.gmail.com:465, SSL, OAuth2, true

   account6:
     INCOMING: account6, , (imap) imap.gmail.com:993, SSL, OAuth2
     OUTGOING: , smtp.gmail.com:465, SSL, OAuth2, true

   account7:
     INCOMING: account7, , (imap) imap.aol.com:993, alwaysSTARTTLS, passwordCleartext
     OUTGOING: , smtp.aol.com:587, alwaysSTARTTLS, passwordCleartext, true

   account8:
     INCOMING: account8, , (imap) imap.aol.com:993, alwaysSTARTTLS, passwordCleartext
     OUTGOING: , smtp.aol.com:587, alwaysSTARTTLS, passwordCleartext, true

   account9:
     INCOMING: account9, , (imap) imap.aol.com:993, alwaysSTARTTLS, passwordCleartext
     OUTGOING: , smtp.aol.com:587, alwaysSTARTTLS, passwordCleartext, true

 Crash Reports
   https://crash-stats.mozilla.com/report/index/bp-12b15dae-0f3d-4649-ad73-c48410170817 (8/17/2017)

 Extensions
   Lightning, 5.4.3, true, {e2fda1a4-762b-4020-b5ad-a41df1933103}

 Important Modified Preferences

   Name: Value

     accessibility.lastLoadDate: 1506396912
     browser.cache.disk.capacity: 358400
     browser.cache.disk.filesystem_reported: 1
     browser.cache.disk.smart_size_cached_value: 358400
     browser.cache.disk.smart_size.first_run: false
     browser.cache.disk.smart_size.use_old_max: false
     dom.apps.reset-permissions: true
     extensions.lastAppVersion: 52.3.0
     font.name.monospace.el: Consolas
     font.name.monospace.x-cyrillic: Consolas
     font.name.monospace.x-unicode: Consolas
     font.name.monospace.x-western: Consolas
     font.name.sans-serif.el: Calibri
     font.name.sans-serif.x-cyrillic: Calibri
     font.name.sans-serif.x-unicode: Calibri
     font.name.sans-serif.x-western: Calibri
     font.name.serif.el: Cambria
     font.name.serif.x-cyrillic: Cambria
     font.name.serif.x-unicode: Cambria
     font.name.serif.x-western: Cambria
     font.size.fixed.el: 14
     font.size.fixed.x-cyrillic: 14
     font.size.fixed.x-unicode: 14
     font.size.fixed.x-western: 14
     font.size.variable.el: 17
     font.size.variable.x-cyrillic: 17
     font.size.variable.x-unicode: 17
     font.size.variable.x-western: 17
     mail.openMessageBehavior.version: 1
     mail.winsearch.firstRunDone: true
     mailnews.database.global.datastore.id: e3f55609-4bc4-4095-932e-40ea95d02c5
     mailnews.database.global.views.conversation.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"3"},"attachmentCol":{"visible":false…
     media.gmp.storage.version.observed: 1
     network.cookie.prefsMigrated: true
     network.predictor.cleaned-up: true
     places.database.lastMaintenance: 1507419397
     places.history.expiration.transient_current_max_pages: 122334
     plugin.importedState: true
     security.sandbox.content.tempDirSuffix: {fdf24051-f89b-41cd-8a4f-e4507cdb15d1}

 Graphics

     GPU #1
     Description: Intel(R) HD Graphics 620
     Vendor ID: 0x8086
     Device ID: 0x5916
     RAM: Unknown
     Drivers: igdumdim64 igd10iumd64 igd10iumd64 igd12umd64 igdumdim32 igd10iumd32 igd10iumd32 igd12umd32
     Driver Version: 21.20.16.4664
     Driver Date: 4-21-2017

     Features
     Direct2D: false
     DirectWrite: true (10.0.15063.413)
     WebGL Renderer: Google Inc. -- ANGLE (Intel(R) HD Graphics 620 Direct3D9Ex vs_3_0 ps_3_0) -- OpenGL ES 2.0 (ANGLE 2.1.0.2a250c8a0e15)

     AzureCanvasBackend: skia
     AzureCanvasAccelerated: 0
     AzureFallbackCanvasBackend: cairo
     AzureContentBackend: skia

 JavaScript

 Incremental GC: 1

 Accessibility

   Activated: 0
   Prevent Accessibility: 0

 Library Versions

     Expected minimum version
     Version in use

     NSPR
     4.13.1
     4.13.1

     NSS
     3.28.5
     3.28.5

     NSS Util
     3.28.5
     3.28.5

     NSS SSL
     3.28.5
     3.28.5

     NSS S/MIME
     3.28.5
     3.28.5

Thanks!

PS: the Gmail accounts are working. Thanks

account7: INCOMING: account7, , (imap) imap.aol.com:993, alwaysSTARTTLS, passwordCleartext

For the IMAP accounts use SSL/TLS for 'Connection security' instead of STARTTLS.

Thank you so much, that fixed it! I think Matt may have been trying to tell me the something similar but I didn't understand. Anyway, much appreciated!