: Look at the bottom-left corner icon. If it shows a "disconnected" computer, click it to go back online.
Thunderbird might be set to only download headers, or it may not be checking for new mail frequently enough. For IMAP Accounts thunderbird do not download messages
: Click the Get Messages button (cloud icon) in the top-left corner to force a check. : Look at the bottom-left corner icon
: Use a site like DownDetector to see if your email provider (Gmail, Outlook, etc.) is currently having an outage. Adjust Account Synchronization Settings For IMAP Accounts : Click the Get Messages
Top Ways to Fix Thunderbird Not Downloading Messages It’s frustrating when Thunderbird stops fetching your latest emails. Whether you’re missing a few messages or everything has come to a standstill, the cause is usually a simple setting or a minor technical glitch. Quick Fixes to Try First