What do these Visual Studio 2005 Performance Tool/Wizard/Session errors mean?

Question

In attempting to use the Performance Tools on an ASP.NET website I'm getting various combinations of these errors (depending on what I attempt to do to fix them):

1. The web site could not be configured correctly. Configuring '\web.config' failed. Access to the path '\web.config' is denied. - I can make this dissappear by checking-out the web.config file or unsetting the read only attribute
2. The web.config file for the site http://localhost:0/ contains information from a previous run. The web.config file was generated, so deleting it should fix the issue. - Why is it using port 0? I can't find this setting anywhere. A 'normal' run uses a specified port, e.g. 4549
3. The web.config file \web.config has been changed and backup information was lost. - What?!

Any ideas?

I'm running Visual Studio 2005 with TFS 2005, it's an ASP.NET 2.0 Web Application Project.

Answer 1

I found a solution to the above errors which allows me to use the sampling profile method but there is another, possibly unrelated problem when I try to use the instrumentation profile method.

As in the original question - just check-out the Web.config or remove the read-only attribute, this fixes error 1.

To fix errors 2 and 3, remove the lines below from your Web.config:

<appSettings>
    <add key="microsoft.visualstudio.teamsystems.aspnetdevserver:/" value="3311;True;3204;1" />
    <add key="microsoft.visualstudio.teamsystems.backupinfo" value="1;web.config.backup" />
</appSettings>
<runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
    </assemblyBinding>
</runtime>

Answer 2

I was getting "The web.config file for the site http://localhost:0/ contains information from a previous run. The web.config file was generated, so deleting it should fix the issue" in Visual Studio 2008 when I tried running a unit test for a web service method. I had a Web.config file in my web service's project directory, but that wasn't the one getting modified. Turns out, I had passed the wrong argument to AspNetDevelopmentServer and it was sticking web.config in other directories. Here are the two lines I had to put above my unit test method (in addition to [TestMethod], of course):

[AspNetDevelopmentServer("MyWebService", @"MyWebServiceProjectDirectory\")]
[UrlToTest("http://localhost/MyWebService/MyWebService.asmx")]

Now I can run the unit test fine. Before, it would run fine once, then give me that web.config error. Now, it runs fine multiple times without complaining about the web.config file.