Problem Backup Exchange Server 2007SP3 UP6 with NMM2.4.0.375

Hello,

since two weeks my exchange backup ist not running succesfully.

OS: W2K8R2 SP1 englisch

EXC: 2007 Standard SP3 UP6 englisch Version8.3(Build 83.6)

Roles: only mailbox role

Storage Groups: 4

MBDBs: 4

Networker Client: 7.6.3.5.Build.891

NMM2.4.0.375

Networker Server: 7.6.3.5.Build.891

History: for two weeks switch the tape library to a new storage node, no more configuration changes

I checked out the following community awnsers. Also that one with the editing the registry keys for keep alive.

Re: Nmm fails with error 'Traditional save returned error. saverc :-1'

Has someone an idear? That will be greate? My last backup is from 18 Apr 2013. This is also able to recover over the NMM.