I'm trying to attach a database (.mdf) within the Object Explorer in Toad for SQL Server 5.6 and I get the following error:
Toad for SQL Serve can't recognize a valid MDF file or file may be in use. Try to select a different files and make sure the files are detached
The file is not attached to anything, so it is not in use and the SQL Server file is compatible with the version being run.
Attach Database function doesn’t work on Case Insensitive servers with the described error. No matter if mdf/ldf files were renamed or not.
Refer to the steps in the attached document, “Attach DB Workaround.doc”.
Waiting for fix to be released in a future version of Toad for SQL Server.
If you have issues with the renamed mdf/ldf files, as a workaround for this, use the Rename Database action from Object Explorer context menu instead of the detach/attach action.
Logged Defect for this issue is ST90434. See solution SOL80914