Yes, I was looking forward to seeing an article that would show REAL alternatives for Outlook - not for Outlook Express (or Windows Mail nowadays, I think). This article only lists some well-known email clients with just a fraction of the MS Office Outlook functionality.
As for Thunderbird I have seen several cases where the email database has crashed resulting in several hours of recovery work. Even a simple task like moving the application to another computer has been a nightmare.
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