If you're interested in seeking out and obliterating these nasty files (well, moving the valuable content that they contain to Office 365 mailboxes), then you might like the 2nd edition of a free eBook on the topic authored by Paul Cunningham and edited by me. Available from QUADROtech at http://www.quadrotech-it.com/pstbook/
On the other hand, if you like PSTs then you should ignore this message...
