Scaling On Surface Pro 4 - Please Help

Hi,

Please help me fix the GUI scaling on Calibre when using a surface Pro 4. The GUI looks too small on this tablet when booting without an external monitor connected. With an external monitor connected, I can open and move Calibre to the tablet screen and the GUI looks and scales perfect...I can even detach the tablet from the monitor and it still scales fine, but as soon as I reboot or just boot without an external monitor connected the Calibre GUI and viewer scale too small.

I did what Microsoft recommends by going into the program properties and disabling auto scaling feature, but that does not help.

Please help.