Windows 7 - Outlook 2007 cannot open and print email messages

A customer called me because he could no longer open and print email messages in Outlook 2007. He is running Windows XP SP3 with 3.5 gigs of ram and a dual core processor. The system struggles a little but doesn't seem overwhelmed by how he loads it. The computer was also throwing up a low virtual memory error. For starters I:

1. closed Outlook and ran disk cleanup. Then I manually emptied the user and Windows temp folders.
2. Set the swapfile to the recommended size (it was too small) and rebooted.

Afterward Outlook seemed more responsive. It didn't have a problem sending/receiving and it was possible to view messages in the preview pane, however it still would not open a message in a separate window and it wouldn't print messages (I confirmed that the printer worked fine by printing from another application)

I located all the PST files, one of which was 11 gigs. I installed PerfectDisk, analyzed the disk for fragmentation and discovered that the 11 gig PST was fragmented into over 30 thousand pieces (the others weren't much better). I started the defrag and told the customer it would take all day.

It seems to me that the extreme fragmentation of the PSTs is causing the problem, but I haven't heard yet if defragging solved it. Would you agree? If I hear from the customer that the problem is not solved what else should I be looking at? TIA

Run scanpst... it will fix!

More info: Repair Outlook Data Files (.pst and .ost) - Outlook - Office.com

Thanks, this is the next step I may need.

It has solved EVERY Outlook issue with non-opening Outlook for me... I too support many users! This WILL get it done! Dont waste your time with defrag, it will NOT work on a pst file! Stop it and use scanpst!