Kraig,
It's not related to your SetupBuilder signed executable, nor to the certificate.
See the following links:
http://www.lindersoft.com/forums/sho...3758#post73758
http://answers.microsoft.com/en-us/w...0-d7d29834c14a
http://answers.microsoft.com/en-us/w...0-6a3008f92712
Especially this part: "I opened Explorer, found and opened Tools on the top menu bar and launched Internet Options. I then clicked the Advanced tab and then found "Reset Internet Explorer settings to their DEFAULT condition." I then lastly clicked the [Reset] button for this."
Hope this helps a bit.
Friedrich