Outlook Slow? Compacting Your PST File Could Help

Has Outlook been slow to open for you lately? Maybe "compacting" the PST file could help:

"When you empty the Deleted Items folder, all the deleted messages disappear — but they are still in your PST file. While Outlook periodically reclaims that wasted space in the background, you can manually initiate the process, too. This makes good sense after you have emptied the Deleted Items folder for the first time after a lot of spam, or if you have just moved a year's worth of mail to your archive PST, for example."

Heinz Tschabitscher, About.com Guide to Email, has all the details:

How to Compact a PST File to Reduce Its Size in Outlook