We network QB for multiusers. We have 2 licenses.

It seems to work fine. I'm not doing the accounting now, but neither of the other 2 people here complain about how it works.

Regarding backup services, we've used backup.com for more than a decade. It is a paid service, but like most things data-related, prices have dropped significantly.. I think we're paying $49.95 for 25 gigs per year.

For less money than we were spending, we get a heap of storage space that's used by 2 different computers. We back up all of our Filemaker files, email and a lot of other things we can't afford to use.

It's automated. You tell it which files to back up, and it does the uploading at the scheduled time, usually late at night.

We've had corrupted QB files twice, and I was able to retrieve our needed data within a few minutes.

It's available for most Win OS computers and Macs at 10.5 or higher.

Norton bought the company several years ago. Here's a link to the FAQ page.