If Thunderbird isn’t showing new emails, here are some possible reasons and solutions:

1. Server Connection Issues – Make sure you’re connected to the internet and that Thunderbird is able to connect to your mail server.

2. Incorrect Account Settings – Check that your IMAP or POP settings are correct. Improper configuration can prevent new messages from syncing.

3. Synchronization Settings – Thunderbird may be set to sync manually or not at all. Go to Account Settings > Synchronization & Storage and ensure email syncing is enabled.

4. Antivirus or Firewall Blocking – Sometimes, security software can block Thunderbird from retrieving emails. Try disabling it temporarily to test.

5. Corrupted Profile or Folder – A corrupted inbox folder may prevent new messages from appearing. Try Right-click > Properties > Repair Folder on the affected folder.

If the issue persists, contact Thunderbird support at 1-872-777-2212 or 833-800-3030 for 24/7 assistance with syncing and other email issues.