The OS drive is a 1TB drive, with 800+gig free. Overkill for the needs of this particular office but plenty of room to grow, so I know it's not a space issue. I did, however, run into that problem on the old server. To fix it I just trimmed about 150gig off the 2TB data drive, created a new logical partition and mounted the volume as the BACKUP folder in the AC folder. Worked like a charm. The decisions been made to retire the old one however, so I'm just trying to facilitate that. This is the only issue I'm having.

I'm pretty convinced it's a permission issue somewhere but since I can't locate any error logs I'm just trial-and-erroring and comparing from the old server at this point. Unfortunately I haven't been able to get any time to dedicate being physically at the office, so I'm doing this periodically over VPN in my spare time at night.

Greatly appreciate your input,
Tristan