Experimente a solução aqui: link
Open gpedit.msc
Browse to Computer Configuration --> Administrative Templates --> Windows Components --> Remote Desktop Services --> Remote Desktop Session Host --> Session Time Limits.
Enable the "Set time limit for disconnected sessions" and set it to "Never".
[I didn't have to do this [next step] but here for completeness]
and change the Local Security Policy under Local Policies -> Security Options -> Interactive logon: Do not require CTRL+ALT+Del" to "Enabled", the problem disappears.