ClickOnce Deployment Issues
I love ClickOnce, but it can be a problem if your application checks for new versions at startup and your connection to the Internet is down. One problem reported was:

The details button gave me lots of information, but the primary part was this:
ERROR SUMMARY Below is a summary of the errors, details of
these errors are listed later in the log. * Activation of C:\DOCUME~1\RBRIGH~1.RAN\STARTM~1\Programs\Startup\WALLPA~1.APP resulted in exception. Following failure messages were detected: + Exception reading manifest from http://intralink.domainnamechanged.com/proxy1.html: the manifest may not be valid or the file could not be opened. + The 'br' start tag on line 4 does not match the end tag of 'center'. Line 7, position 3.
This is very misleading. The root problem was just that my proxy server settings were wrong on my laptop. I don't think these error messages would help you discover that.

