Hello Chad,
Thanks for your message, I'm sorry you are having problems with vbCodeShield. As you mention Windows XP SP2, the problem is possibly related to Data Execution Protection.
A knowledge base article is available from the URL below which may help you resolve this issue:
http://www.innovasys.com/support/kbarticle.aspx?key=2286
If you have any other questions, please don't hesitate to contact us.