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Thunderbird not connecting to server. It says timds out and an error occurred connecting to mobile.charter.net. I can neither send or receive emails. This started 8/20/2026

I find that my desktop browser firefox is very slow or doesn't work at all on a lot of websites like amazon or fortnine.

My internet connection and computer are not the issue: 270Mbps (wired connection) Processor AMD Ryzen 7 9800X3D 8-Core Processor (4.70 GHz) Installed RAM 32.0 GB (31.1 GB usable) Graphics card NVIDIA GeForce RTX 4070 Ti SUPER (16 GB) Storage 3.58 TB of 10.92 TB used System type 64-bit operating system, x64-based processor (Windows 11)

My old PC and my mobile phone runs these website fine.

Sometimes the website will work for a moment, but stop and just load for ever after I open a new tab or clink a link. My task manager doesn't show any ethernet usage despite the tabs indicating they are trying to load. Refreshing the tabs does nothing and no matter how long I leave them they don't load. All my drivers, OS and programs are up to date. I have disabled my enhanced tracking protection and I don't have any adblockers. I have tried using the CMD "ipconfig -renew" and using ccleaner to clear out my cookies and cache but, nothing seems to have any lasting effect.

I am losing my mind trying to fix this. Why can I not browse the internet on my PC?

Any help on this would be amazing and much appreciated.

Sincerely, Calvin

Hi!

We have a intranet site that works in Edge and Chrome without issues with the site added to "internet options". But for some reason we are getting 401 Unauthorized when trying to access it from Firefox. I have tried adding the urls to: network.automatic-ntlm-auth.trusted-uris network.automatic-ntlm-auth.allow-proxies: true network.automatic-ntlm-auth.allow-non-fqdn: true network.auth.force-generic-ntlm: false network.auth.force-generic-ntlm-v1: false

Ingocnito mode , same error. I have tried disabling all plugins. Disabled DNS over HTTPS.

HTTP/1.1 401 Unauthorized Server: Microsoft-IIS/10.0 WWW-Authenticate: Negotiate X-Powered-By: ASP.NET Date: Mon, 25 May 2026 08:15:41 GMT Content-Length: 0

Regards Rasmus

I have Thunderbird on the old computer. For twenty+ years I have read the instructions for moving it to the new computer. i cannot understand/am not at all confident in my ability AND I have only ONE keyboard/mouse. I have to move it from one computer to the other to operate them.

Right now all email is on the old computer, no email is on the new computer. No email has ever been on my cellular telephone. One set of periforals - keyboard/mouse.

I DO have the Bravura, the Plugable transfer cable and accompanying software, and many other things came across, but not the Thunderbird.

I want to do the move/installation correctly so that not one stored email is lost or corrupted.

I need help.

My Thunderbird (windows) is really not working, so I want to reinstall the whole thing. I have 4 accounts and a local folder. I don't want to backup all the profiles before reinstalling, as I am having an annoying issue with g-mail (I don't HAVE a gmail any more, but Thunderbird wants to login to gmail every time I open it). I only want to backup the "local" folder, as, so I want to reinstall the accounts one by one from scratch. In that way I hope, I can purge Thunderbird of the gmail. Now the question: How do I backup the local folder in a way that makes it easy to import it back after all the reinstallment?

I started noticing that Firefox was giving me a lot of "not responding" freezes the past couple of weeks. The past couple of days I basically cannot access Firefox at all - constant, immediate freezing. I have tried uninstalling/reinstalling (multiple times), disabling hardware acceleration, running troubleshooter mode (still freezes! if it opens at all!), deleting profiles, restarting my computer, etc. I've done just about everything I can find online about this issue. Nothing has worked. I have no issues with Chrome or Edge.

Any suggestions??

Gentlemen, isn't your browser using a lot of RAM? I've been freaking out about it in recent years. That's only with 25 tabs open!! Despite the fact that the system was installed just a day ago, without any tweaks!!!

Neither my wife nor I can access email on our respective PCs. This has been the case for four weeks. We can access email by our Android phones, but we really want to use our PCs. I've tried to resolve the problem and failed. Previous to this failure, I had an account with BT but this was transferred to EE. When I attempt to log in to my mail account, I receive the message "Could not connect ... :the connection was refused". I can also add is that in my Account settings, Outgoing Mail server I see a message "Connection to server mail.btinternet.com:465 failed."

recent firefox update can no longer copy and paste when creating a blog post in Squarespace, I have been using squarespace for around 15 years for my websites and I have never seen this issue, Firefox 15.1 installed and all of a sudden when trying to create a blog post in Squarespace, when I right click a text box pop up and it no longer says paste so I can no longer copy and paste text - this is more than a little annoying, you will not be surprised to know that I am now using Chrome to create my posts, there is no issue in chrome. I am a firefox geek! how can i solve this problem, I just did another update from Firefox, the issue remains I have been using computers for 40 year so I am not a novice but software glitches, I am lost

I have followed the instructions that several people give to transfer my existing Thunderbird installation to a new computer where I have just installed Thunderbird. That is I copied the Thunderbird folder and put it in the Roaming folded found in %appdata%. Both computers are on Windows 11. When I open the new Thunderbird, it does not recognise it. Furthermore, in Help>Troubleshooting information>Profile folder when I click to open the folder, it looks for a folder that is not in my previous Thunderbird installation: qr19mupe.default-release instead of the one that came with my imported Thunderbird folder. Has this happened to anybody and found the solution? Can anybody help please?

When I try to make a Google search I get the following message, "I'm not a robot" with a reCAPTCHA: "Our systems have detected unusual traffic from your computer network. I know this has been an ongoing issue, but it only happens with firefox on both my computers, vpn and all extensions off. Even tried a new IP address, same issue.

Each time I open TBird, I get a message at the bottom left of the screen telling me that TBird has deleted X number of messages. I do not want TBird to ever delete any messages. How do I turn this automatic delete function off?

Not sure if I picked the correct topic for this...

I had to reinstall Windows 11 on my PC as the old copy was corrupt to the point I could not install updates, even with Microsoft's help. Before I made the plunge, I used Tools -> Export to create a zip file on my D:. After installing Thuderbird on the rebuilt copy, I went to Tools -> Import to recover everything.

About 19% in, I received error "Import failed unexpectedly, more information may be available in the Error Console." I found the Error Console but don't know how top proceed.

Initial messages: module is not a constructor ExtensionCommon.sys.mjs:1679:15 EmptyDatabaseError: "blocklists/addons-bloomfilters" has not been synced yet Database.sys.mjs:19:5 NS_ERROR_ABORT: Password dialog canceled 2 MsgIncomingServer.sys.mjs:923:24

Messages at the bottom of the console: Uncaught (in promise) NS_ERROR_FILE_NOT_FOUND: Component returned failure code: 0x80520012 (NS_ERROR_FILE_NOT_FOUND) [nsIFile.copyTo]

   _recursivelyCopyMsgFolder resource:///modules/ThunderbirdProfileImporter.sys.mjs:781
   _recursivelyCopyMsgFolder resource:///modules/ThunderbirdProfileImporter.sys.mjs:772
   _mergeLocalFolders resource:///modules/ThunderbirdProfileImporter.sys.mjs:745
   _importServersAndAccounts resource:///modules/ThunderbirdProfileImporter.sys.mjs:354

ThunderbirdProfileImporter.sys.mjs:781:19 1785523577301 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/26c785ea-2226-4024-9b0e-cf44ce2860f7/first-shutdown/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523577301 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 26c785ea-2226-4024-9b0e-cf44ce2860f7: {"isTrusted":true} Log.sys.mjs:722 1785523577302 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/bc5b8fd6-8907-4169-9e98-2c732d265c20/main/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523577302 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping bc5b8fd6-8907-4169-9e98-2c732d265c20: {"isTrusted":true} Log.sys.mjs:722 1785523577302 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/01ee7ef8-942d-4fbd-a404-debd99ad5e4d/new-profile/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523577302 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 01ee7ef8-942d-4fbd-a404-debd99ad5e4d: {"isTrusted":true} Log.sys.mjs:722 1785523577325 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/1f64b615-ed65-4a65-8853-7bd3e3077b54/health/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523577330 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/26c785ea-2226-4024-9b0e-cf44ce2860f7/first-shutdown/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523577330 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 26c785ea-2226-4024-9b0e-cf44ce2860f7: {"isTrusted":true} Log.sys.mjs:722 1785523577331 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/bc5b8fd6-8907-4169-9e98-2c732d265c20/main/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523577331 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping bc5b8fd6-8907-4169-9e98-2c732d265c20: {"isTrusted":true} Log.sys.mjs:722 1785523577331 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/01ee7ef8-942d-4fbd-a404-debd99ad5e4d/new-profile/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523577331 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 01ee7ef8-942d-4fbd-a404-debd99ad5e4d: {"isTrusted":true} Log.sys.mjs:722 1785523577334 Toolkit.Telemetry WARN TelemetryStorage::_scanArchive - have seen this id before: 1f64b615-ed65-4a65-8853-7bd3e3077b54, overwrite: false pop3.server1.1: NetworkTimeoutError: a Network error occurred Pop3Client.sys.mjs:381:18 pop3.server1.1: SecurityError info: Pop3Client.sys.mjs:441:20 pop3.server1.1: SecurityError cert chain: imap.email.comcast.net; serial# 5F:F9:03:A2:A2:B8:A3:45:AE:17:FE:A1:C9:15:D6:45 <- Norton Web/Mail Shield Root; serial# 2F:61:CC:98:EC:34:F2:43:99:93:5B:E6:A0:A5:DF:E2 Pop3Client.sys.mjs:446:22 1785523697961 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/1f64b615-ed65-4a65-8853-7bd3e3077b54/health/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523697961 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 1f64b615-ed65-4a65-8853-7bd3e3077b54: {"isTrusted":true} Log.sys.mjs:722 1785523697962 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/26c785ea-2226-4024-9b0e-cf44ce2860f7/first-shutdown/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523697962 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 26c785ea-2226-4024-9b0e-cf44ce2860f7: {"isTrusted":true} Log.sys.mjs:722 1785523697962 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/bc5b8fd6-8907-4169-9e98-2c732d265c20/main/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523697962 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping bc5b8fd6-8907-4169-9e98-2c732d265c20: {"isTrusted":true} Log.sys.mjs:722 1785523697963 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/01ee7ef8-942d-4fbd-a404-debd99ad5e4d/new-profile/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523697963 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 01ee7ef8-942d-4fbd-a404-debd99ad5e4d: {"isTrusted":true} Log.sys.mjs:722 1785523947429 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/1f64b615-ed65-4a65-8853-7bd3e3077b54/health/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523947429 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 1f64b615-ed65-4a65-8853-7bd3e3077b54: {"isTrusted":true} Log.sys.mjs:722 1785523947430 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/26c785ea-2226-4024-9b0e-cf44ce2860f7/first-shutdown/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523947431 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 26c785ea-2226-4024-9b0e-cf44ce2860f7: {"isTrusted":true} Log.sys.mjs:722 1785523947431 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/bc5b8fd6-8907-4169-9e98-2c732d265c20/main/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523947431 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping bc5b8fd6-8907-4169-9e98-2c732d265c20: {"isTrusted":true} Log.sys.mjs:722 1785523947431 Toolkit.Telemetry ERROR TelemetrySend::_doPing - error making request to https://incoming-telemetry.thunderbird.net/submit/telemetry/01ee7ef8-942d-4fbd-a404-debd99ad5e4d/new-profile/Thunderbird/153.0.1/release/20260728090639?v=4: eUnreachable Log.sys.mjs:722 1785523947431 Toolkit.Telemetry ERROR TelemetrySend::sendPersistedPings - failed to send ping 01ee7ef8-942d-4fbd-a404-debd99ad5e4d: {"isTrusted":true} Log.sys.mjs:722

I have an image copy of my old installation. Can I simply locate the Thunderbird profile on the backup and restore it?

Within the past day or so, which means 7-18-26 or later, some of my email messages on thunderbird for my pc have a "From" description that is not correct. I look at the messages, and the "From" is entirely different than the "From" description when looking at the email message list. I have never encountered this problem before. I'm using thunderbird 152.0.1 64-bit on my pc.

As the topic says, the message list turned from the usual dark-mode look, to a full black background after updating to 151.0.

Was this an intentional change? How can I revert it?

I successfully linked / synced the thunderbird calendar with the iCloud calendar. Calendar entries manually entered in iCloud or iPhone calendar are successfully synced and are visible in the thunderbird mail. The other way round, syncing the existing entries in the Thunderbird calendar does not work. They do not appear in the iCloud or iPhone calendar. Searching the internet, the specific Thunderbird or Apple help-sites did not provide an obvious solution for this problem. I went through all (or nearly all) recommendations given by Apple, no success to sync from Thunderbird to iCloud.

Any suggestion what to modify or adjust

jm

Until recently the folder pane could be sized or hidden via the double-headed arrowed cursor. Shortly after the 151.0.1 update this stopped working. All suggested solutions have not worked. A full uninstall (Revo Uninstall) and completely new profile has not fixed the problem. Folder pane only responds to the menu setting and is only Open/close but no sizing.

I'm blaming the latest Firefox update from a couple of days ago, since this problem only arose yesterday. Now cut off from reading and following news that I really want to receive.

This is what I get when trying to access links within a few of the websites that I regularly access for links to articles it posts:

The site ahead may contain harmful programs

Firefox blocked this page because it might try to trick you into installing programs that harm your browsing experience (for example, by changing your homepage or showing extra ads on sites you visit).

Advisory provided by Google Safe Browsing.