Thank you for the fast reply. I do understand that when the company file is switched to single user the other computer will no longer be able to access the file until it is restored. My issue is that when the file is switched back to multi user mode in QuickBooks on the hosting computer, the second computer is still not able to login to the company file. I have tried closing QuickBooks and also rebooting the computer. The only way for the second (non-hosting) computer to login is for the hosting computer to close QuickBooks, the second computer then logs with the file under single user mode, switches to multi user mode, and then computer 1 can log back into QuickBooks. I hope this makes more sense. Thanks again!