TFS 2010 - The server returned content type text/html, which is not supported error, solution?

I have a setup a new TFS 2010 build definition. When I run the build for this build definition I get the following error during a "GET" operation:

"The server returned content type text/html, which is not supported"

13:48
 Overall Build Process    
00:00
Update Build Number    
00:00
Create th开发者_StackOverflowe Drop Location    
13:46
 Run On Agent (reserved build agent [Test] Agent - xyzbuild)    
00:00
Delete Test Results Directory    
00:00
Delete Binaries Directory    
03:24
Delete Workspace    
00:00
Delete Sources Directory    
00:01
Create Workspace    
10:11
 Get Workspace
 C:\Builds\7\xyz\[Test] TFS 2010 xyzbuild\Sources\Source Code\xyz\Help\Help.aspx: The server returned content type text/html, which is not supported.

The TFS 2008 builds which have been migrated to the new TFS 2010 server work fine, the problem is with only the new TFS 2010 build definition.

Has anyone else faced a similar problem? Any solutions?

We did migration from TFS 2008 to TFS 2010. I have logged a support incident with Microsoft and they have confirmed that it is a bug with TFS 2010 server.

I'd expect that you are getting an error of some variety back from the web service which is why the get operation is seeing a text/html content type being returned instead of the actual file contents.

Can you check that your build service account has permissions to get the Help.aspx file from source control? Try logging in as your build account and then doing a tf get $/path/to/help.aspx from the command line and seeing if that works.

Can you also check the event log (on both the build and tfs servers) to see if there's anything showing up in there.