Compact Thunderbird Folders

[OLD] Compact Folders in Thunderbird to improve performance and reliability

To compact folders manually:

1. Open Thunderbird.
2. Select Compact Folders from the File menu.
3. Wait for the folders to compact.

To compact folders automatically (recommended):

1. Open Thunderbird.
2. Go to Tools > Options > Advanced > Network & Disk Space > Disk Space.
3. Set Thunderbird to "Compact folder when it will save over 100 kB".
4. Click OK.

More information about compacting folders in Thunderbird is available here:
http://kb.mozillazine.org/Compacting_folders