I have exactly the same issue.
"Application has been blocked from accessing Graphics hardware."
"Application Microsoft Windows Operating System has been blocked from accessing Graphics hardware."
Old dumb big screen monitor. It's the ROKU box stopping access.
Model: 3930X - Roku Express
Serial Number: X00400SJPR6A
SW Ver: 11.5.0 - Build 4312-AE
Hi HW_Eng,
Welcome to the Roku Community.
We're here to help. Could you tell us when did you receive this error message, is it from the beginning of the connection or after some time got connected, and are doing specific actions from your Windows device? For troubleshooting purposes, have you tried connecting a different Android or Windows device to your Roku device to see if there's any difference?
Keep us posted on what you find out.
Regards,
Nimfa
I had been using mirroring with my Roku box for about a week. Two days ago it stopped connecting. The 'blocked' message appears when I try to connect, after selecting Connect - "Roku Express". The laptop thinks it is connected, displaying 'Connected to Roku Express' in a top of the laptop screen ribbon. The monitor displays a horizontal purple status bar that shows about 98% complete across the screen, not quite completing anymore. Text on the monitor says "Starting video from ... Desktop-xxxxxxx" where the x's are my desktop ID. There is a "Stop Video" icon on the monitor. Pressing Roku remote control keys does nothing or terminates the connection. Pretty odd that it worked so well then just quit.
Casting from YouTube still works great. Only the mirroring is blocked. I have power cycled and even done a factory reset on the Roku box. Nada.
So I got another laptop and could mirror with it. At least for now. This makes it really challenging to see what changed. And I have to admit, the ROKU box likely isn't the cause. Doh! Hardware is easy. Windows - way too many traps. After a full day of trying different things, my first laptop still won't mirror with no apparent setting changes. Guidance would be appreciated.
