Can you, please, specify how that built in mail program (you assume Outlook 2k) accesses e-mails? Does it read some pst file or it accesses Exchange server traditional way?
If it opens some kind of files, I thinking about bat file association in your OS. Can you, please, specify more your problem with DLL errors?
Thank you,
Ondrej Zilinec - Cievo
...Good question is half of the answer...