QuickBooks 2009 update error 12007 generally shows up due to QuickBooks update time out. There can be other reasons also such as if the software doesn't get access to the server thus this error shows up when QuickBooks can't connect to the internet. Usually, a firewall, antivirus, or browser may be causing an issue and not letting QB connect to the internet.
It mostly comes when users try to download QuickBook updates or payroll.
QuickBooks Error 12007 occurs at the time when a user tries to update QuickBooks desktop or try to make any changes to the QB payroll service function. The other possible reason behind to this error is the inability of accessing the internet connection through your desktop.