Thunderbird Community Forum

I use Thunderbird on a Mac, where Gmail is my default email. When I try to send an email, it often takes 10 tries before it goes through, due to timeouts. How can I fix this?

In initial set up of Thunderbird laptop: on the last screen of set up, after entering username and password, Thunderbird set up posts a green background notice: " [checkmark] Configuration found in Mozilla ISP database." When "Done" is selected, a the following yellow background notice is posted: "Unable to log in at server. Probably wrong configuration, username or password." I know username and password are correct; they allow access to email via Spectrum webmail. I am confident configuration is correct [IMAP] \,because that is the configuration I have always used with my Thunderbird account on other computers. Suggestions?

I've been running TB for 10-12 years, generally with no problems. When I logged in on 5/13/26, I saw that Windows had run an overnight update:

    2026-05 Security Update (KB5089549) (26200.8457)

Thunderbird (version 147.0.2.0) was not running, although it had been when I slept the PC the previous night.

Now, when I try to start TB it gives me the crash report dialog. Selecting the Restart option just brings me back to the crash report.

In searching for possible causes, I see that this may be caused by a bad profile. So I open the profile folder with (run) %APPDATA%\Thunderbird\Profiles\ which in my case is:

  C:\Users\<user_name>\AppData\Roaming\Thunderbird\Profiles

This is an empty directory. But if I go up one level to \Thunderbird there is a profile.ini file which contains (actual user ID replaced by <user_ID>:

[Install8216C80C92C4E828] Default=E:\Thunderbird\Profiles

[Profile0] Name=<user_ID> IsRelative=0 Path=E:\Thunderbird\Profiles Default=1

[General] StartWithLastProfile=1 Version=2

"E:\Thunderbird\" is the correct location of my TB installation. In that directory is a profile.ini file that contains:

[General] StartWithLastProfile=1

[Profile0] Name=default IsRelative=1 Path=Profiles/<user_ID>.default

Directory "E:\Thunderbird\Profiles\<user_ID>.default" is present. But all of it's files are dated 2010 except Mail, dated 2016.

Directory "E:\Thunderbird\Profiles" contains the ImapMail and Mail sub directories totaling about 25GB data.

I don't know what the Thunderbird startup process is or if this all looks correct. Can someone give me a sanity check? If this looks normal, what else could be corrupted?

Thanks in advance.