I have got the error message "The file xxxx.pst is not a personal folders file". Someone told me that it occurs due to the header of your PST file is damaged. If it is true, then How can I fix it?
You have got this error message due to PST file corruption, you can use Scanpst.exe tool to fix PST errors. There are numerous third party Outlook PST repair software available on Web that can help you to repair corrupt PST file. You can also try one of them to solve your issues.