When logging into OPSSQL a user may get the following error:

Problem:

sqlnet.ora has the following entry: SQLNET.AUTHENTICATION_SERVICES= (NTS)

Resolution:

The work around for this is to set the SQLNET.AUTHENTICATION_SERVICES= (NONE) in the sqlnet.ora file
In Windows Explorer, go to the local hardrive (E: in this case) to E:\Oracle\Ora81\Network\Admin\sqlnet.ora

Save changes and close sqlnet.ora and log back into OPSSQL.