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i have a problem in the connection we need to have remote session

• Client : Mozilla Thunderbird (version utilisée) • Serveur SMTP : smtp-mail.outlook.com • Port : 587 • Sécurité : SSL/TLS • Authentification : OAuth2 • Message d’erreur exact indiquant un timeout / échec de connexion SMTP • Confirmation que : o le compte fonctionne en webmail o le service Microsoft est accessible o le problème persiste malgré un changement de réseau (si testé)

One of my two outlook email accounts no longer appears in Thunderbird, which says it is authenticated but not connected. This happened suddenly. I can still get the messages by going onto outlook.com. How do I get it back on Thunderbird?

I'm getting "Thunderbird can't connect to the server" message, so I can't download messages. However, a message or two will finally download 1-2 hours later.

Same problem on 2 laptops, both running Windows 11. But I know my emails are coming in as I can view them via Spectrum webmail. So the problem isn't the Spectrum servers.

I've logged out and back into Thunderbird, and have re-booted my laptops. No luck. What to do?

Also, is there a place to report problems directly to Thunderbird?

Thanks for any help.

After system complete reinstallation Ubuntu 24.04 it is not possible to send mails with SMTP Server. Receiving messages is possible!! Two fault Messages happen, I've two SMTP servers: 1. No connection to SMTP possible 2. Server timeout

And yes, I've checked nearly everything what's to find in the internet, reinstallation, change and check settings and passwords, together with the specialist from my provider. Also my provider is not able to find a mistake. As I've found out in the net, there are sometimes problems to connect to SMTP, but no solution found. Is there some security in the UBUNTU system, which blocks the SMTP connection or is this a bug from Thunderbird? Thanks in advance Andreas

I have spent most of two days trying to Thunderbird to send email. It has worked perfectly for years. Suddenly, emails end up in Sent folder but go nowhere. My email host service sees nothing wrong. I can send emails through webmail and usually through Outlook. I have spent most of the day getting coached by Copilot and I am quite sure I have all the settings the way that worked flawlessly until two weeks ago. Is Thunderbird just dead and I need to go to Outlook?

I have no idea why Thunderbird stopped working for me and I can't seem to solve the problem - one day. I got a notification to re set my credentials - nothing since

Hello,

I recently upgraded to a new PC from Windows 10 to Windows 11. For some reason I can not open links in any emails, even if right clicking them. I have gone through all steps here: http://kb.mozillazine.org/Standard_diagnostic_-_Thunderbird but nothing has changed. I have disabled Win Defender completely and still no change.

Any idea what I am missing? I am at a loss at this point.

Thanks for any advice or direction.

For over a year, my browser occasionally loses connectivity. It may work for 3 hours or 3 days, but inevitably new tabs will stop working and then slowly the others will stop as well. When this happens, none of my other browsers are impacted. They work fine. It is only Firefox. The only solution is to close everything and lose all my work.

Once I do that and restart Firefox, I receive an error message telling me I am using an older version of Firefox that is not compatible with my profile. The only solution that brings me back to the best starting place is to re-install Firefox.

My company IT spent 3 days trying to find the problem and couldn't. I have uninstalled and reinstalled so many times. All extensions are turned off, as are the two add-ons. I have been using Firefox for over a decade and prefer it to all other browsers, but I need to find a solution or I am going to have to move on. Help!!!

As of this morning I am no longer able to download or send email via my Spectrum email account. A warning message appears next to the account name reading 'The certificate for mobile.charter.net:993 does not come from a trusted source.' The section from the View Certificate page makes it seem like the certificate should be valid:

Issuer Name

Country BE Organization GlobalSign nv-sa Common Name GlobalSign RSA OV SSL CA 2018 Validity Not Before Tue, 19 May 2026 11:45:30 GMT Not After Fri, 04 Dec 2026 11:45:30 GMT . Spectrum of course says it's an issue with my email client. Adding an exception for mobile.charter.net does work, but that doesn't seem like a good long-term solution. When I attemt to get a certificate for the server, I get a 'No Information Available - Unable to obtain identification status for this site'. I am not using a mail scanner and my only anti-virus is Windows 11 built-in Virus & Threat Protection. Any help or suggestions would be appreciated, thanks.

I keep getting prompt with this message stating the current config is set to block cookies (attached screenshot) and is occurring every interval. I had updated the app yesterday, some how after restarting the computer, it's popping up with the message.

Hi there, it seems I'm suffering from the same problems as others in several countries. I have also not been able to access my gmx.com account via Thunderbird for about a week now. I live in Belgium and use a Proton VPN, in case this is relevant. I can't find how to delete cookies in history, nor any other potential solutions to the problem. Any help offered is greatly appreciated! Best, Doreen

Cannot send or receive email all of sudden in Thunderbird. When I the click the messages icon, nothing happens, and I get "Could not connect to server mail.twc.com; the connection was refused". When trying to send a m,message I get "Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) mail.twc.com failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again." No settings were changed and everything was fine when I put the computer to sleep. This happens on both a Win 7 and 11 machine Email is a Time Warner (now Spectrum) Road Runner account (twc.com). Spent an hour with Spectrum, and they say this is a third party (Thunderbird) issue. A friend has the same setup, and is having the same problems that started at the same time. Win 11 version 150.02 Win 7 115.18.0 (latest available for win 7)

Appreciate any help....

[Edit:] I'm using Kubuntu with Thunderbird installed via flatpak using the flathub repo.

When attempting to add my calendars on our Nextcloud server, I can't get further then the second dialog.

Steps to reproduce: 1. New account > Calendar 2. Select "On the network" 3. Enter the correct user name and address (I did try the server address AND both CalDAV addresses presented in the calendar settings on the Nextcloud web app). 4. Press "Search for calendars" 5. After an extended period of time a dialog with a title "Adding a security exception" appears, claiming, that our Nextcloud site does not have a correct certificate (it does).

This is where the journey ends. If you add an exception, the dialog disappears and you are still at number 3. Trying again will produce the same result. Funny thing is, that you can press the button "Load certificate" in the "exception dialog" and then the same dialog will declare that our site does indeed have a correct certificate! But it will only allow you to close the dialog and you are still at number 3 and without any chance to add your calendars.

This is a completely new installation of Thunderbird. There are other folks that are using Thunderbird with their calendars on the same Nextcloud server and everything works happily. I presume this is a bug with the newer version of Thunderbird or something of that sort.

Considering migrating from Outlook to Thunderbird (TB), as it is a logical potential path. Best I can tell from AI input is placing my message store on a network share (colocated, stable network), would likely be unreliable. Said that TB storage format was basically fragile and subject to corruption if there was any kind of hiccup in the data transfer or if something happened during a power outage for example. Wanted to see how the real community felt about that and if it was indeed inadvisable to do so.

I have 12 browsers (except Google Chrome) on my 3 android mobile phones, all OnePlus Nord and CE.

I am having problems with FireFox to open websites. I have tried all troubleshoots using AI but nothing is working. I have reinstalled FireFox multiple times, still the error remains the same. See four screenshots (note the date, time stamp on the images), I cannot connect to: google.com, yahoo.com, wikipedia.org or vedicstore.com, the error in words is the same.

FireFox version on all 3 phones is:

1. 153.0.2 (Build #2016175759), 70679dc17d13e6a5082805d9823d62ece968cd81 GV: 153.0.2-20260730155536 AS: 153.0 OS: Android 14

2. 153.0.2 (Build #2016175759), 70679dc17d13e6a5082805d9823d62ece968cd81 GV: 153.0.2-20260730155536 AS: 153.0 OS: Android 16

Any help from the peers here to make FireFox work will be highly appreciated. Thanks a million to one and all.

A FireFox user from Trinidad and Tobago, West Indies

Hello Firefox Support Team,I am facing a persistent issue where Firefox is unable to open or connect to any Public IP addresses, resulting in a "Connection Reset" error. This issue happens simultaneously on two different operating systems: Windows and Linux (on the same network).Interestingly, the same Public IP addresses open completely fine and without any issues on Google Chrome.I have already tried the following troubleshooting steps, but none of them resolved the issue:Disabled HTTPS-Only Mode completely.Disabled Secure DNS (DNS over HTTPS).Changed Network Settings to "No Proxy".Set "security.tls.version.min" to 1 and enabled deprecated TLS.Disabled HTTP/3 and HTTP/2 in about:config.Performed a full Firefox Refresh (Safe Mode / Default Profile).Since the issue persists across different OS platforms only on Firefox, it seems to be related to how Firefox handles direct IP handshakes compared to Chromium-based browsers.Please advise on how to resolve this. Thank you.

Hello,

I am trying to set up my email account on Thunderbird for Android, but the incoming server configuration fails during the validation step.Error Message Received:"Checking incoming server settings failed.

Authentication error. The server returned the following message: User is authenticated but not connected."

My Environment & Setup Details: App Version: Thunderbird 21.0 OS: Moto Edge 50 Neo, Android 16 Email Provider: Outlook.com Server: outlook.office365.com Protocol: IMAP Authentication Method: OAuth2.0

I have tried so far: Toggled between Wi-Fi and mobile data to rule out local network issues. Verified that my login credentials work perfectly via the webmail browser interface. Completely deleted the account attempt and retried the automatic setup process from scratch.

I have attached a screenshot of the exact error screen for reference. Any guidance on how to fix this authentication loop would be greatly appreciated.

This issue has been persistent for many months now.

If any more info is needed, please feel free to reach out. Thank You

Firefox Nightly for Android

After one of recent update (few weeks ago) cannot access local network ip addresses.

Tried different suggestions from SO in about:config but nothing helps.

Other browsers works.

I recently switched from Debian to Fedora Workstation. Everything works fine, even better under Fedora, except Firefox. There is this quirk, where whenever I wake up my system from suspension, and I try to search something, Firefox just shows a loading sign as if it was loading the page, but I see via the inspect tool that it isn't even sending any HTTPS requests to the server. I know this problem specifically affects Firefox, because other programs that require an internet connection, such as fetching mail via Thunderbird or installing packages via DNF work completely fine. In order to get Firefox to actually work, I have to completely close and reopen the application, forcing me to lose unsaved work in some cases. I've tried everything, from restarting my machine to waiting to see if it will be patched in a future update, but nothing has gotten better. Please help me. Thank you in advance.

Been struggling to get any of the 4 different accounts from PennTeleData at my body shop to connect to thunderbird. They were working yesterday and all of a sudden no good this AM. I can access my PTD email through their web browser and they don't have any support for a 3rd party program. Sure wish there was someone to call at mozilla. I have exhausted soooo many different options all to no avail. Any advice or questions for me to better let you know what my issue is?