Hi,
This problem most likely occurs because the PST file is corrupted. Some data in the file was modified and it is considered to be password-protected.
There is a utility called scanpst.exe (or the Inbox Repair Tool) that you can use check for corruption and possibly repair the PST file. For more information, please refer to the following
Knowledge Base article.
How to use the Inbox Repair Tools to recover e-mail messages in Outlook 2002 and Outlook 2003 (287497)
http://support.microsoft.com/default.aspx?scid=KB;EN-US;287497
Regards,
Scott Atkins MCSE, MCSA
Partner Technical Lead - Outlook
Microsoft Technical Support
for Platforms and Business Applications
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