Two installations of AeroFS on the same machine is not supported. In other words, if you have Windows 7 and Windows 8 OS on the same machine, you cannot have two separate instances of AeroFS, one running within each operating system.
The databases will get very confused, and more importantly, as the two OS are never on at the same time, the two instances of AeroFS cannot be on at the same time, so files between the two installations will never fully sync.
To ensure that your machine successfully syncs with other devices using AeroFS, we recommend that you install AeroFS on one and only one OS of your choosing.
If you have inadvertently installed multiple AeroFS on multiple operating systems on the same device already, please Unlink all of them and reinstall.