IIS7 URL Rewrite breaks for URLs containing + characters
Solution 1:
The '+' symbol is really not valid URL encoding for a space. TeamCity should be encoding them as %20.
Either way, the error is probably a result of a common requestFiltering security setting in IIS7.
Try the following command:
%windir%\system32\inetsrv\appcmd set config /section:requestfiltering /allowdoubleescaping:true
It should stop IIS from returing 404's for anything with a + in the URL.
Solution 2:
As h0tw1r3 already answered, you have to disable URL validation.
If you want to do it on IIS server level then use the command below:
%windir%\system32\inetsrv\appcmd set config /section:requestfiltering /allowdoubleescaping:true
If you want to disable it only on application level, then you need to just add the following section to your web.config file:
<system.webServer>
<security>
<requestFiltering allowDoubleEscaping="true" />
</security>
</system.webServer>