Since I upgraded my client computer to Windows 10 I would get small Icons and fonts when I have to restart host Windows 7 computer remotely and logging through RDP session. In that case it looks like 125% DPI set on host computer is ignored. If I log locally after restart/reboot first, remote session respects 125% DPI.I tried RDP client ZOOM setting Zoom Windows 10 Remote Desktop connections to older versions of Windows to improve your experience on a hi-DPI client display
but it doesn't work in Full screen mode and quality of display is bad.Than I stumbled upon You cannot change the DPI setting through a Remote Desktop session on a computer that is running Windows 7 or Windows Server 2008 R2. Applying the Hot Fix to host computer with Windows 7 resolved the problem for me.