Error While dropping OEM Schema

Error: 

For Dropping OEM Schema in Windows:

C:\Users\Chinni>C:/app1/Chinni/product/11.2.0/dbhome_1/BIN/emca -deconfig dbcont
rol db -repos drop -SYS_PWD Password123 -SYSMAN_PWD Password123

STARTED EMCA at Aug 11, 2013 10:48:48 PM
EM Configuration Assistant, Version 11.2.0.0.2 Production
Copyright (c) 2003, 2005, Oracle.  All rights reserved.

Enter the following information:
Database SID: MIGDB
Listener port number: 1521

Do you wish to continue? [yes(Y)/no(N)]: Y
Aug 11, 2013 10:49:08 PM oracle.sysman.emcp.EMConfig perform
INFO: This operation is being logged at C:\app1\Chinni\cfgtoollogs\emca\MIGDB\em
ca_2013_08_11_22_48_48.log.
Aug 11, 2013 10:49:09 PM oracle.sysman.emcp.util.DBControlUtil stopOMS
INFO: Stopping Database Control (this may take a while) ...
Aug 11, 2013 10:49:09 PM oracle.sysman.emcp.util.PlatformInterface executeComman
d
WARNING: Error executing CMD /C C:\app1\Chinni\product\11.2.0\dbhome_1\bin\nmesr
vops.exe delete OracleDBConsoleMIGDB
Aug 11, 2013 10:49:09 PM oracle.sysman.emcp.EMConfig perform
SEVERE: Can't find file C:\app1\Chinni\product\11.2.0\dbhome_1\Chinni-PC_MIGDB\s
ysman\config\emoms.properties
Refer to the log file at C:\app1\Chinni\cfgtoollogs\emca\MIGDB\emca_2013_08_11_2
2_48_48.log for more details.
Could not complete the configuration. Refer to the log file at C:\app1\Chinni\cf
gtoollogs\emca\MIGDB\emca_2013_08_11_22_48_48.log for more details.

Solution: 

This error occurs because of permission issues on database.

• Try running command prompt as Administrator.

•  If it is linux provide sufficient permissions for user.

With out error:
C:\Windows\system32>C:/app1/Chinni/product/11.2.0/dbhome_1/BIN/emca -deconfig db
control db -repos drop -SYS_PWD Password123 -SYSMAN_PWD Password123

STARTED EMCA at Aug 11, 2013 10:51:24 PM
EM Configuration Assistant, Version 11.2.0.0.2 Production
Copyright (c) 2003, 2005, Oracle.  All rights reserved.

Enter the following information:
Database SID: MIGDB
Listener port number: 1521

Do you wish to continue? [yes(Y)/no(N)]: Y
Aug 11, 2013 10:51:46 PM oracle.sysman.emcp.EMConfig perform
INFO: This operation is being logged at C:\app1\Chinni\cfgtoollogs\emca\MIGDB\em
ca_2013_08_11_22_51_24.log.
Aug 11, 2013 10:51:46 PM oracle.sysman.emcp.util.DBControlUtil stopOMS
INFO: Stopping Database Control (this may take a while) ...
Aug 11, 2013 10:51:49 PM oracle.sysman.emcp.EMReposConfig invoke
INFO: Dropping the EM repository (this may take a while) ...

Enterprise Manager configuration completed successfully
FINISHED EMCA at Aug 11, 2013 11:49:57 PM

Thanks