Please start *Windows'* safe mode with networking enabled - win8 http://windows.microsoft.com/en-us/windows-8/windows-startup-settings-safe-mode - win7 http://windows.microsoft.com/en-us/windows/start-computer-safe-mode#start-computer-safe-mode=windows-7 - XP http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/boot_failsafe.mspx Still In Windows safe mode, start thunderbird in safe mode - http://support.mozillamessaging.com/en-US/kb/safe-mode Does problem go away?

Hi Shivdath. Can you give us an update please? We'd like to understand and know your situation, even if you resolved it. Thanks