Q: How can I check to see if the patch I installed is going to work correctly for Windows XP. I changed the date to after DST and the time did not change. Is there something else I need to do?
A: If the computer's a member of a domain, make sure you're unplugged from the network or disable the Windows Time service when you roll the date ahead.  Time synchronization may be causing your clock to revert.  You may also want to restart after making the date change, just to be sure (you'll need to log on locally or with cached credentials afterwards).