Rebuild Thunderbird’s global search index when results are blank or slow
What to do first
Recreate only the search database to fix missing or slow results while preserving messages.
This is a general troubleshooting guide, not an announcement of a current outage.
Affected products and symptoms
- Product
- Mozilla Thunderbird
- Versions and conditions
- Thunderbird Desktop
- Error codes and identifiers
- global-messages-db.sqlite
Symptoms
- Existing messages do not appear in global search
- Search is extremely slow or returns blank results
Causes and conditions
The Gloda global-search database may be corrupt, fragmented, or still indexing.
Before you start
- Confirm important mail exists on the server or in a backup
- Provide enough free space and time for the computer to remain on during indexing
Precautions
- Search results are incomplete during reindexing
- Do not mistake message-store files for the search database
Step-by-step instructions
Open the message directly in its folder, then compare in-folder filtering with global search.
If the message itself will not open or a folder is missing, troubleshoot synchronization or folder storage first; rebuilding the global index is not the right first action.
Open Menu > Help > Troubleshooting Information and select Open Folder beside Profile Folder.
Leave that folder open, quit Thunderbird, and verify no Thunderbird process remains. Never change the database while Thunderbird is running.
Move global-messages-db.sqlite to a backup location such as the desktop. Moving it instead of deleting it keeps a rollback copy.
Do not touch Mail, ImapMail, prefs.js, or folder message files. Use the main database as the precise target even if related temporary files exist.
Start Thunderbird. It creates a new global-messages-db.sqlite and begins indexing messages and address-book cards.
Monitor Tools > Activity Manager. Large mailboxes take time, and partial or blank results during that period do not prove failure.
Search for an old unique subject, a recent sender, and a word from a message body.
Rebuilding does not automatically reduce database size. Do not repeat it merely to shrink the file unless fewer messages are being indexed.
Check the result
- Indexing completes in Activity Manager
- Both older and recent messages appear in search
If the problem continues
- If one folder is missing, inspect that folder’s synchronization state
- Test the same account in a new profile to isolate profile-specific damage
Scope of this guide
Troubleshooting guide — Preserve mail data and replace only the search index, then monitor automatic reindexing in Activity Manager.
Frequently asked questions
Can I use mail while rebuilding?
Yes, but performance can be reduced and searches can remain partial until completion.
Will rebuilding shrink the database?
Not automatically. It generally shrinks only when fewer messages need indexing.
Official sources and dates
Source publication or resolution date: Not specified. Sources checked: 2026-09-05. The check date is not the date the problem first occurred. Interface labels can vary between versions and display languages.
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