Open your email provider's web interface in a browser. If new emails show up there but not in Thunderbird, your account configuration or local application data is the root cause. Step 1: Repair Corrupted Folder Indexing
Thunderbird relies on index files ( .msf ) to display your mail. If these index files corrupt, Thunderbird may download new messages but fail to show them in your Inbox. Thunderbird suddenly will not download mail from the server thunderbird will not download new messages
Before altering advanced settings, quickly rule out standard external factors: Open your email provider's web interface in a browser
Check platforms like Downdetector to ensure your email provider (e.g., Gmail, Outlook, Yahoo) is not experiencing a server outage. If these index files corrupt, Thunderbird may download
Open your browser and load a new webpage to verify your network connection .
It is highly frustrating when stops retrieving your new emails. You click "Get Messages," but nothing happens, or you receive a misleading "There are no new messages" alert.
This comprehensive troubleshooting guide covers why this error happens and lists step-by-step methods to get your inbox syncing again. Quick Initial Checks