In Thunderbird, you may receive a “connection to server timed out” error when sending or receiving a message. Connection timeout errors occur when the server takes too long to respond to a request from your device.
You may be able to prevent this error by increasing the length of time the email client will wait for a response from the server.
How to prevent timeout errors in Thunderbird
1. In Windows, open Thunderbird and go to Tools -> Options -> Advanced -> General -> Config Editor.
1. In Mac, go to Thunderbird -> Preferences -> Advanced -> General -> Config editor… Click to confirm “I accept the risk!”
2. In the search field, type in mailnews.tcptimeout.
3. Right click on that row and select Modify.
4. Change the value to a higher number, such as 1000 or 2000.
If you still receive a connection timeout error, there may be something else wrong with your internet connection, your computer, or our servers.