If user has All Connections list open in Connection Manager, and you have two connections with the same name (one is a Windows connection, one is a SQL Server connection). If the Windows connection is above the SQL connection in the list and user tries to delete the SQL connection, Spotlight will highlight and try to delete the Windows connection instead. The below error appears:
"The Diagnostic Server was not able to delete xxxx"
The only way to get around this is to re-sort the lists so the SQL connection is above the Windows connection in the list. This is inconvenient when deleting many connections.
Waiting for fix in future version of Spotlight on SQL Server Enterprise.