I've used Thunderbird on several Windows machines almost since it was first released, and am quite happy with the results.
I've not been totally successful in getting the message filters to file incoming stuff into the expected folder; I'm fairly certain that this is because I've not been able to correctly configure this part of the program. The basic filter sections work well; I've probably asked too much in getting it to 'micro filter' some emails into where I would like them.
Mark me down as a satisfied user
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