I had TB 2.0.0.6 on Fedora 7 system with various plugins (google calendar, webmail etc...).
I updated TB to 2.0.0.9 via the yum update process and none of the plugins are installed any more.
I tried reinstalling them, and every time it says restart TB to complete installation, but after restart still no plugins are installed.

On an impulse I created a new profile in TB and tried installing the webmail plugin, and it is working perfectly in the new profile. I am pretty confident other plugins will work with the new profile as well.

So I guess the upgrade has somehow broken the old/Default profile.

Any ideas on how to fix it please?

Thanks.

Certainly not the most user-friendly solution and I don't know if this would work (so maybe make a backup), but you could start TB with your "old" profile, remove the "old" plugins, scrub the config files and make sure no references to those plugins remain, quit TB, restart it and and then install the new plugin versions?

I tried doing that. But I guess couldn't clean out all the directories and configs. :-(
This is a deeper problem than reworking a profile. We need to ensure that the existing configuration does not break with every upgrade, or atleast there is an easy way to fix it...

Then file a bug report.