Full Backup Unsuccessful

Hello, I'm trying out the managed backup feature to backup an entire network. Unfortunately I'm not having any success and the log only offers:

[snapshot][2016-10-25 18:56:54][Warning] There was an error processing the files

File size is significantly lower than I would expect for a full backup, yet it doesn't give me any errors while running and all the steps appear to complete correctly.

Any thoughts? What should I try next?

Thanks!