hi all,
I just upgraded my database from 9.8 to 10.4. Now I have some TNS issues

if sitting directing on my server and do a
sqlplus user/passwd@InstanceName I get the TNS error

ERROR:
ORA-12154: TNS:could not resolve the connect identifier specified

however my sqlplus connection is fine without the @InstanceName (if my SID is OK)

However all my 3rd party/client tools are connecting fine. TOAD, DBVISUALIZER, client SQLPLUS and users are using the database OK. So I don't think anything has changed in TNS settings?.

As a result I cannot initiate an RMAN backup from this server/instance

Recovery Manager: Release 10.2.0.4.0 - Production on Thu Feb 26 13:26:40 2009

Copyright (c) 1982, 2007, Oracle. All rights reserved.

connected to target database: XXXXXXX (DBID=368783836355)
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00554: initialization of internal recovery manager package failed
RMAN-04004: error from recovery catalog database: ORA-12154: TNS:could not resolve the connect identifier specified

thanks