Although it is important to regularly back up your company file, it is very essential to back up both Acctivate and your Quickbooks files when you are upgrading your version of Quickbooks.
After finishing the Quickbooks update, log into Acctivate and run a sync. Keep in mind that the first sync with the upgraded version of Quickbooks may take much longer depending on if the system needs to verify and rebuild or not. It is suggested to synchronize Quickbooks in single-user mode one time after a major update. After about 24 hours after the first sync, the sync time should return back to normal.