When opening or connecting to an Access .accdb database on Windows 7, the following error is received:
"[Microsoft][ODBC Microsoft Access Driver] Cannot open database '(unknown)'. It may not be a database that your application recognizes, or the file may be corrupt."
The file is not corrupt and opens fine in other PCs.
Access 2010 ODBC driver not installed.
Download and install the "Microsoft Access Database Engine 2010 Redistributable" here.
AccessDatabaseEngine.exe (the 32-bit version)
Note: Toad will only support the 32-bit version. It can be installed on a 64-bit Windows and should not conflict with existing 64-bit Office setup.