Error handling XBAP when certificate is not in Trusted Publishers

I have an XBAP that requires full trust, and my certificate to be located in the Trusted Publishers store.

How can I gracefully handle the situation where the certificate is开发者_开发问答 not located in the trusted publishers store? As it stands now, click once will display a very ugly error message.

I would like to avoid that error, and replace it with instructions for users who don't have that certificate installed.