Now when you are having connection problems use this batch file to start Thunderbird - it will create a log file on your desktop with a file name like thunderbird_20110410_1114.log (ie thunderbird_YYYYMMDD_HHMM.log) when you use it to start Thunderbird.
set mydate=%date:~-4,4%%date:~-7,2%%date:~-10,2% set mytime=%time:~0,2%%time:~+3,2% set NSPR_LOG_MODULES=IMAP:4,POP3:4,SMTP:4 set NSPR_LOG_FILE=%USERPROFILE%\Desktop\thunderbird_%mydate%_%mytime%.log start thunderbird.exe