We are running Win 2012 R2 with a fibre connected Quantum i500 with four IBM LTO-6 drives.
The tape driver is:
Microsoft dated 6/21/2006, v6.3.9600.16384 "IBM ULTRIUM-TD6 SCSI Sequential Device"
IBM does have a newer driver but after several attempts at installing it the drives won't function.
I got the older drivers back in use and the drives work as before. My inner "hardware dude" says stick with this driver until something says it needs to be updated/upgraded. Since our Simpana system is still rather new if a driver should be installed then this would be the time to do it.