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Full user review
"Same problems as earlier versions"
It's reasonably reliable, and is similar in appearance to Outlook Express. Thunderbird has worked well for me on computers that would not run Outlook Express reliably.
When Outlook Express is working properly, it has better text editing and enhancement features than Thunderbird. Thunderbird's interaction with the keyboard buffer is still problematic at times; basically, the cursor can't keep up. Also, if you want a really challenging experience, try exporting Thunderbird's e-mail messages to another e-mail client. For the serious business user, Thunderbird 2.0 is not the way to go in my opinion. Even the webmail clients of several ISPs are better for the business user.