Q: I would like to know how to defrag Outlook 2007. The program is showing 16GB when I try to use normal Windows defragmenter.
A: Outlook data files can get quite large as all of your emails, calendar and contact information is stored in a single location. The Windows defrag tool won’t touch Outlook .pst files because the program has its own Compact option which periodically tidies up the files – you’ve probably seen messages about this when launching the program.
You can try downloading the Contig tool from Windows Sysinternals this runs the old NT defragmentation routine which allows you to target individual files. You need to run it from the command line – instructions are on the webpage – and make sure that Outlook isn’t open during the process. This will merely ensure that the file is stored in a single contiguous location, it won’t do anything to reduce the size. The only way you’ll do that is by deleting or archiving old messages. You can run an archive from within Outlook by going to File/ Archive which will move old messages to a separate .pst file.
Originally featured in PCU140