It works!
When I was looking in the restore section of Windows Server Backup, it didn't show the documents. But, I did a little test-recovery of my own files and the folder with my documents showed up with all of the documents inside.
The user that is doing the backups has to be a part of the backup operators group. That group can evidently backup documents that it doesn't have access too.
Hope this helps someone in the future :)
Personally, I would suggest Get a different backup program -- I don't know much about Windows Server Backup on SBS, but I know that dedicated backup programs are specifically designed for the kind of workflow you're describing.
If you want to try to save costs I'd suggest you shelve your current backup drives and buy new ones, then configure a proper backup rotation.
A "proper backup rotation" would look something like this:
- Every Friday take a full backup of the server. Send that disk off-site on Monday morning.
- Monday through Thursday take an incremental backup - ideally to separate disks like you're doing now - and send those off-site.
You would need at least 6 disks (Monday through Thursday incremental backups, and two Friday "Full" disks) for this process, and would scratch each disk as you reuse it.
The idea is to always have one "Full" backup set off-site that will allow you to restore to your current state (either last Friday's full backup, or the previous week's full set of disks).
Basically each disk is treated as a (very large) virtual tape in this situation. Depending on how much data you have to back up you may be able to store several weeks of backups on the disks by configuring the backup software appropriately.
As Grant pointed out in his comment, YOU ALSO NEED TO PERFORM RESTORE TESTING when you set up your new backup rotation.
Based on your question I can't tell if you do restore tests regularly, but it sounds like you don't (otherwise you would know for certain if you really need all of your disks for a restore). Backups that have not been restore tested effectively don't exist, and testing them in an actual emergency where you need to recover the system is a Bad Idea because if they don't work you're in a really bad situation.
The usual recommendation is to perform a restore test quarterly, or any time you change the backup set or system configuration.
Best Answer
As Evan Anderson's comment says, Windows Server backup uses VSS to store backups unless it's writing to a network share. This is why your backup storage disk is hidden from Windows explorer (and you, unless you're using specialized tools): VSS wants to choose where to write the backups.
Because VSS isn't supported on UNC destinations, you'll only be able to keep a single backup if you back up to a share.
Other possible issues include (C&Ped from Microsoft's docs):
I'd recommend using a specific disk solely for backups.