Screen resolution reset after workspaces reboot

​@Augustin Here is how to reset your screen resolution in Workspaces:

https://docs.aws.amazon.com/workspaces-thin-client/latest/ug/managing-display-resolution.html

Hi Aaron and thanks for your answer.

Changing the screen resolution is not a problem : I just have to connect to the VM and it is back to 1080*1920

The only problem is that when rebooted this resolution is reset to 1024 × 768 (screenshot is taken as 1040 × 744 but there is the windows taskbar)

​@Augustin You will need to find a way to have your Workspaces VM reset its screen resolution after reboot. 

Per Claude:

The best fixes, in order of preference:

Option 1 — Fix it in the client (easiest, per-user)

In the WorkSpaces client, go to Settings → Display → Display Resolution and specify 1920×1080. This sets a fixed resolution that won't change even when the client window is resized. To re-enable automatic resizing later, choose "Adapt automatically."

This is the cleanest solution if the user controls their own client settings.

Option 2 — Set it via a logon script (best for admin-enforced, fleet-wide)

If you're managing a fleet of Workspaces and want it enforced for everyone, a Group Policy logon script is the way to go. You can create a GPO in your WorkSpaces Active Directory domain, navigate to User Configuration → Policies → Windows Settings → Scripts (Logon/Logoff) → Logon, and attach a PowerShell script that runs at each login. AWS

The script itself can use the registry approach, which is more reliable than Set-DisplayResolution:

reg add "HKEY_CURRENT_USER\Control Panel\Desktop" /v ScreenSizeX /t REG_DWORD /d 1920 /f
reg add "HKEY_CURRENT_USER\Control Panel\Desktop" /v ScreenSizeY /t REG_DWORD /d 1080 /f
RUNDLL32.EXE USER32.DLL,UpdatePerUserSystemParameters
```

The `ScreenSizeX` and `ScreenSizeY` values of 1920 and 1080 respectively control the resolution, and calling `UpdatePerUserSystemParameters` applies the change without a full reboot. 

---

**Option 3 — Lock it server-side via registry (admin on the Workspace itself)**

If you have admin access to the Windows Workspace, you can lock the minimum resolution so DCV never drops below 1920×1080:
```
reg add "HKEY_USERS\S-1-5-18\Software\GSettings\com\nicesoftware\dcv\display" ^
  /v min-head-resolution /t REG_SZ /d "(1920, 1080)" /f
```

And optionally, to prevent the DCV client from resizing the resolution at all:
```
reg add "HKEY_USERS\S-1-5-18\Software\GSettings\com\nicesoftware\dcv\display" ^
  /v enable-client-resize /t REG_DWORD /d 0 /f

You can also set a default layout so DCV always starts sessions at 1920×1080 using the console-session-default-layout registry key.