... I can't even create an update to check it with.
Are you getting this error in wyBuild? If so, can you send me your wyBuild project file (*.wyp)? Send it to wyatt@wyday.com.
Are you getting this error when you click "Build wyUpdate" or "Build Updates"?
What version of Windows are you using? Are you an admin user? Is your computer altered using the Group Policy Editor?