I patched one of my oracle databases through EM Gridcontrol and received a succeed message but upon further investigation I found this in the log file.

Thu Apr 20 10:20:33 2006 - Attempting to apply patch to Oracle home (G:\oracle\product\10.1.0\oracle_home)...

Thu Apr 20 10:20:34 2006 - Could not locate emdpatch.pl... Fallback to OPatch

---------- Error Message ----------
Error: 004
Could not find etc\config\inventory to apply patch
----------- End Message -----------

Thu Apr 20 10:20:35 2006 - Patching failed.

any idea???