My wife emailed me a PST file that she wanted archived to our RAID array. It was easier for her to email it. However, Outlook blocked the attachment because of the PST extension, as it does for many extensions. Some of the blocking I find irritating and a little paranoid.
Here's how to unblock blocked attachments.
(Substitute the appropriate version numbers for your installation, 12 is 2007, 11 is 2003, etc.)
Add a registry string value under HKEY_CURRENT_USER\Software\Microsoft\Office\<VERSION>\Security called Level1Remove and add the extensions you want with leading dots and trailing semicolons like:
.pst;.rar
And all is well.
Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. I am a failed stand-up comic, a cornrower, and a book author.
Disclaimer: The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.