TL2000 - iSCSI connection to R520 server

Recently I inherited a TL2000 that was connected to an old HP Proliant DL380 G4 Server via iSCSI. I detached the TL2000 and connected it to our R520 Server (running Server 2012 R2) via iSCSI. I was able to make a successful connection and updated the firmware for the iSCSI bridge, the TL2000 and the tape drive. I also updated the drivers for the TL2000 and the IBM Ultrium 3580 tape drive in the OS. Everything was coming up Milhouse until I tried to run a tape backup from Backup Exec. 

I cannot write to a tape or erase a tape. I was able to perform an inventory originally and run a cleaning job but that's not working now either. When I try to erase a tape, for instance, I can see on the TL2000 status that it says ‘rewinding’ then ‘writing’ then flips to ‘calibrating’ then back to ‘writing’ until it finally stops then reports that the tape is bad, which is not the case. It also says the drive needs cleaning which is also not the case. I installed a new cleaning tape with a new barcode and was originally able to clena the drive. I also inserted a few new tapes to see if I could write to them. I still get a ‘bad tape’ reported if I try to erase it or write to it plus the status gets changed to 'needs cleaning'.

I contacted Symantec (Veritas) support and it was determined that this is a hardware issue. The robotic library and the tape drive show up in Backup Exec and they also appear in the Device Manager.

Everything also appears to be ok in the iSCSI initiator, both targets are connected. I'm not familiar with iSCSI so I'm a bit out of my element here. 

I also ran the IBM Tape Diagnostic Tool and it gave everything a pass except that a tape cleaning is required, which it doesn't actually need.

I did find in the System Windows logs multiple errors like 'Source: iSCSIPrt, Event ID 10 - Login request failed. The login response packet is given in the dump data'.

Any help would be appreciated.