After downgrading a 6.3 backup archive client to a 6.2 client, the dsmcad process will not start.
Following a successful install of the 6.2 client (having first installed and then removed the 6.3 client) and then running 'TSM Tools for Administrators' and selecting to start the dsmcad, a message is displayed stating that a newer version of the Client Accepter Daemon is already installed.
On install, the backup archive client installer updates the file /var/db/receipts/com.ibm.tivoli.tsm.dsmcad* with the 6.3 receipt. This file is not removed when the 6.3 client is removed via the uninstall process. This is per design, but also causes the above problem when it is desired to downgrade the client in the event of a problem.
Resolving the problem
Removal of this file will allow the dsmcad process to be started via the 'TSM tools' interface.