From MozillaZine Knowledge Base
- This article was written for Thunderbird but also applies to Mozilla Suite / SeaMonkey (though some menu sequences may differ).
If the "Unified Folders" view doesn't seem to work:
- See if the same problem occurs using View -> Folders -> All Folders. If it does, then its not a Unified Folders specific problem, and you need to figure out what type of problem it is. Disappearing mail , Empty folders or Phantom folders might be a good starting point. Otherwise go back to using Unified Folders and try the next suggestion.
- Right click on "inbox" at the top of the folder pane (the inbox that has child folders for each accounts inbox) and select "Properties". Check that the search criteria uses the radio button for "Match all messages" and that there are no additional criteria. Typically you'll see a greyed out "Subject" "contains" and a empty field followed by the plus and minus buttons.
- Try running in safe mode using "Help -> restart with add-ons disabled" to rule out it being a problem due to an add-on.
- Use "Help -> Troubleshooting Information -> Show Folder" to display the contents of the profile using windows explorer (or whatever file manager you are using). Then exit Thunderbird and delete the "smart mailboxs" directory within the Mail directory. Start Thunderbird.
- If deleting "smart mailboxs" doesn't help exit Thunderbird and delete both "smart mailboxs" and the virtualfolders.dat file. That file is used for Saved Search (aka virtual folders) settings. A side effect is that if you had any saved searches they will be deleted and you will have to recreate them. The reason for deleting the file is Unified Folders is a "advanced folder view" that uses saved searches. Restart Thunderbird.
- If none of this works try installing another version of Thunderbird in a different directory and see if it has the same problem. It will reuse your existing profile. Go back to an old version of Thunderbird has instructions on how to find older versions of Thunderbird. You could also download a beta or earlybird version from this web site, though thats a calculated risk as they are not production versions. You may want to backup your profile first using something like Mozbackup
Unified Folders was called Smart Folders in Thunderbird 3.0.*