New installed 1709 Box does not support 4K resolution

[TechnoMax]

I installed a new Windows guest with 1709 and the guest additions 5.2.1 (on the webpage it is still called 5.2.0).
My maximum resolution is 1920 x 1440 in the guest windows and I cannot change to portrait anymore landscape is greaed out. The host Windows has 2160 x 3840. In the past never had these restrictions.

[mpack]

In the UI (not he VM), try setting File|Preferences|Display|Maximum Guest Display Size to None.

[TechnoMax]

This did not help. And neither the third menu pint proposal (I tried 2160 x 3000)

[flyweg]

Hi, I had a similar issue. This resolved it for me. I followed these instructions first.

In the UI (not he VM), try setting File|Preferences|Display|Maximum Guest Display Size to None.
This then let me go to the guest and set the screen resolution to something way bigger than my monitor could handle.

I shutdown the guest then went back and set the Maximum Display Size to Automatic again.
Restarted the guest and the screen resolution was working dynamically as it did before.