I haven't solved the problem, but here is what I've deduced thus far. Since all other three machines play nicely together except the new one, it has to be the new machine. I've checked all the system BIOS times and they are with in a couple minutes of each other, same with the new Windows 8.1 OS. Since I've used this machine before with Win 7 and BtSync successfully, it has to be the new OS that's causing the problem. Which leads me to believe that it is either the Time Zone setting on the new OS or BtSync is not fully compatible with Windows 8.1 yet. I'm going to check the time zone tonight when I get home. Can you tell me where BtSync stores all the user information and such on a Windows based OS, Win 7 and up? Reason I ask is because when I removed BtSync last night to reinstall it, it automatically was attempting to connect to the other machines without mi inputting the share secret. Leads me to believe there is some residual footprint that the application leaves afte install. Thanks