Stop Thunderbird From Asking For a Password Using AOL Or Gmail IMAP Accounts

IMAP is far superior to POP, and AOL and Gmail both support IMAP.  If you are using Gmail or AOL mail with Thunderbird via an IMAP connection, Thunderbird may start asking for your password over and over again.  This can be because Thunderbird is creating too many simultaneous connections to the server.  The fix it to force Thunderbird to pipeline all updates in one single connection, which can make updating folders a little slower but fix this annoying bug.  Here's how:

• Click Edit > Account Settings 
  
• Find the account which has the problem and click Server Settings
  
• Click > Advanced
  
• Change Maximum Number of server connections to cache to 1.

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