I have following setup:
- A Windows 7 client
- A Windows 10 Pro server that has RDP enabled
The client is connecting via RDP to the server.
For years, it was possible that that the Windows 10 Pro had a large DPI scaling (250%).
But suddenly, 1 week ago, the DPI scaling has been reset to 100%, and cannot be changed anymore (error message "The display settings can't be changed from a remote session"). I Googled for hours and tried every fix I could find, e.g. the Registry setting "IgnoreClientDesktopScaleFactor". Nothing helps.
The weird thing is that no updates on the Win7 or Win10 machine was applied. I don't see any cause why the DPI scaling has been disabled.
I have read here that "Remote Desktop Connection Manager" would solve the problem, however, this tool cannot be downloaded from Microsoft anymore, because there is a security vulnerability...
I also tried a Windows 10 => Windows 10 RDP connection, both with normal RDP application, and RDP "app" from Microsoft Store. Both don't support DPI scaling either.

