On the TFS Project Portal, you get a 404 error from SharePoint instead of the dashboard.
Then that project were probably created with the Visual Studio Scrum 1.0 template, and that template is not available on the new SharePoint server.
How to fix
- Download and install Visual Studio Scrum 1.0
- In the Project Portal subfolder, look at Readme.txt
- Execute the batch commands listed in that Readme.txt to upload the missing .WSP file
(on the first line, starting with “SET STSADM”, make sure to replace version “12” with “14” if you are using SharePoint 2010, or accordingly for any newer versions).
(Big thanks to Trevor Hancock, Hassan Fadili, and Wes MacDonald for the solution.)