Actual message was "Cannot open database "Current71020092" requested by the login."
I could not find this exact problem documented. I found a fix.
Following steps to rebuild the analysis server cube, drop and recreate the analysis server cube, and drop both analysis server cube and the tfs_warehouse database resulted in the exact same error.
Fact#1 If you try to make a connection to SQL Server and you specify an "initial catalog" aka database, and the database does not exist or you don't have rights, the login will fail.
Fact#2 Somehow every time the analysis server cube was rebuilt, the data source connection string was created with an Initial catalog of this random database name that did not exist: Current71020092
Here is the STR and fix.
1. Connect to MS Analysis Server instance 10.50.2500 for TFS 2010 with SSMS 2008 R2 10.50.1790
2. Navigate Databases..TFS_Analysis..Data Sources..TFS_AnalysisDataSource
3. Rt-Mouse Properties.
4. Inspect Connection String. Verify that the Initial Catalog= has the CurrentNNNNN database name.
5. Modify the initial catalog to the TFS_Warehouse database for your installation.
Provider=SQLOLEDB.1;Data Source=.;Integrated Security=SSPI;Initial Catalog=tfs_warehouse
6. Use the Web Services Client to invoke Full Analysis processing. It will now succeed.
Chip