The junk mail filter, especially when set on High, is very good at getting rid of most of the spam. You should not import old blacklists into Outlook 2003 since many of the domains will be caught with Outlook's native filter. As you receive mail that is wrongly tagged as spam or is missed, add it's address or domain to the correct filter.
After well over 6 months of using Outlook 2003 and the junk filter on High, the Blocked senders list contains exactly 1 address – an address I use for testing purposes. On the other hand, the Safe senders list contains a number of newsletter and retailer domains.
Published October 31, 2003. Last updated on May 21, 2011.