Error "S_TF_NO_TAPE_PRESENT" when backing up to HP StoreOnce Catalyst

Hello,

we first had an error "0xe00084ec - A backup storage read/write error has occurred" when backing up to HP StoreOnce Catalyst.
After that we did a Software Update for the StoreOnce VSA and have seen that disk space was low.
We manually deleted some old backup sets in Backup Exec and the Housekeeping funktion of StoreOnce cleaned the files.

But now when backing up we receive the error in subject "0x2000040d - S_TF_NO_TAPE_PRESENT"

Does anybody know how to resolve this?

We are using Backup Exec 2012 SP4, Windows Server 2008 R2

StoreOnce is a StoreOnce VSA with software version 3.11.4

OST Plugin Version is 2.0.1

Regards