Hi Mike,
Thank you for using the community.
Normally, this kind of error will occur when we debug an ASP.NET
application which locates on outside web site. However, from your
description, you debug the application on the same server? Is my
understanding correct?
I also suspect the problem is related to the ISA server. You can Open IE,
click Tools/Connection. In the Lan Settings, have you set a proxy server
here? If so, you need to check the "Bypass Proxy server for local
addresses". Additionally, you may try to add the web site to the Trust
Sites to see if it will help.
Furthermore, you may refer following article, it include some basic trouble
shooting steps for this kind of problem:
http://msdn.microsoft.com/library/de...us/vsdebug/htm
l/vxtbshttpservererrors.asp
Luke
Microsoft Online Support
Get Secure!
www.microsoft.com/security
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