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I get error "Could not find Mozillza runtime" when I try to start Thunderbird.

  • 2 replies
  • 5 have this problem
  • 38 views
  • Last reply by GayzeN

acac
acac
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Thunderbird stopped and that error came suddenly when I wasn't using the computer. So it was not a response to anything I had done. Clicking the desktop shortcut gives the same message. I shutdown the computer and restarted. Same thing.

I found the file Thunderbird.exe in the Mozilla Thunderbird folder. When I try to run it I get the same error. It is 481 kb and dated 11/26/2015.

I received a message about an update probably last week but put off restarting the computer so it still hadn't updated to my knowledge. With that date I presume this thunderbird.exe file was downloaded with the update since it should be running on something older.

Anyway, what should I do to bring Thunderbird back to life. Thanks!

Thunderbird stopped and that error came suddenly when I wasn't using the computer. So it was not a response to anything I had done. Clicking the desktop shortcut gives the same message. I shutdown the computer and restarted. Same thing. I found the file Thunderbird.exe in the Mozilla Thunderbird folder. When I try to run it I get the same error. It is 481 kb and dated 11/26/2015. I received a message about an update probably last week but put off restarting the computer so it still hadn't updated to my knowledge. With that date I presume this thunderbird.exe file was downloaded with the update since it should be running on something older. Anyway, what should I do to bring Thunderbird back to life. Thanks!

All Replies (2)

Toad-Hall
Toad-Hall
  • Top 10 Contributor
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Clearly an update had occurred, but may not have worked corectly or TB was exited before it completed...maybe..who knows.


Uninstall Thunderbird: Settings > Programs and Features Select Mozilla Thunderbird ad click on 'uninstall' OR Delete the directory either : C:\Program Files\Mozilla Thunderbird or if using 64 bit : C:\Program Files (x 86)\Mozilla Thunderbird

Clear your browser cache and the Windows Temp directory. Shutdown any anti-virus software you are running. Download a new copy of the full installer from :

Run the installer. Restart the anti-virus program.

Note that your saved messages, address books, settings, passwords, etc (if any) are stored in a different directory from the program files and will not be removed by deleting the directory/uninstalling Thunderbird.exe

GayzeN
GayzeN
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I'm having the same issue.

It was definitely a failed update that did it. I first got a message that the update could not be installed, and then when I tried to open Thunderbird afterward, got the mozilla runtime error above.

I attempted to follow the above instructions, but am unable to uninstall Thunderbird. I went through Windows 8's version of add/remove programs, tried to uninstall. Nothing happened. I then clicked "uninstall" again and it told me I had to wait till the program uninstalled, though it never called up the uninstaller.

It wound up locking up my computer's functions, the uninstaller/etc was not showing up in Task Manager, and I had to shut down and reboot. As soon as the computer came back up, Thunderbird's updater started running again, saying it could not install the "partial update". It is currently stuck on "connecting to the server" (has been like that nearly 20 minutes) and not downloading anything. I'm unable to shut it down. I go to Task Manager and can find nothing to do with Thunderbird or Mozilla updates in the Processes, yet it seems like it's still "stuck" in some sort of failed installation mode.

I recall in the old days we could just delete a file called xpicleanup.exe and try installing again, but that file no longer seems to exist.

HELP. I need Thunderbird for my work, have many quicktext files for my clients, and add-ons that allow me to function. I've lost an entire day's pay to this issue, and it appears that Thunderbird's faulty current update has run amok. Plus, it's the day before Christmas Eve and on top of all this, I have cookies to bake!

UPDATE: Well, being unable to uninstall, I did what I know you shouldn't do when you have a program problem. I tried installing the full update download over top of the broken one. So far, knock wood, it appears to have worked. If problems arise down the line, I'll report back.

Off to bake cookies with my fingers crossed.

Happy Holidays, all.

Modified by GayzeN