OEM - Unable to access Recovery Catalog

Problem: Managing the Production database from Oracle Enterprise Manager Grid control. The recovery catalog is available, the database is registered in recovery catalog, but still OEM gives an error,

	Error
	Only databases with a version number equal to 10 or above, or databases that use a recovery catalog of schema version 10 or above are supported. You can click the following link to register the database in a recovery catalog. Register Database In Recovery Catalog

Solution:
1. In recovery catalog database server, login rman with catalog option.

$> rman catalog sysman/******
RMAN> upgrade catalog;

recovery catalog owner is SYSMAN
enter UPGRADE CATALOG command again to confirm catalog upgrade

RMAN> upgrade catalog

recovery catalog upgraded to version 10.01.00
DBMS_RCVMAN package upgraded to version 10.01.00
DBMS_RCVCAT package upgraded to version 10.01.00

RMAN>

Now if you refresh the OEM page and go to maintenance(T) -> manage current backup URL, it'lll work.

Reference:
Note:298466.1 - Cannot Manage Current Backups with Grid Control even when Recovery Catalog is used