Server 2025 Display Issues

Solution mentioned by re:Post agent is available from this article, and requires the installation of Amazon DCV which is available at no additional charges. In addition, DCV supports higher screen resolution. Try installing DCV as per article and connect using Boumgar

If you are unable to install DCV, you may want to contact BeyondTrust for a solution. Alternatively, try connecting with Bomgar, login to Windows, change to higher display resolution and reboot. After Windows has started, connect and verify if your higher resolution is preserved.

The display resolution issue you're experiencing with Windows Server 2025 is likely related to the remote access tool you're using. When connecting to EC2 instances via third-party remote access tools like Bomgar/BeyondTrust, the default resolution can sometimes be limited to lower settings like 800x600, especially when no physical monitor is attached (which is the case with EC2 instances).

There are a few potential workarounds you can try:

1. For Windows Server instances, you can modify the registry to set a custom resolution. Try adding or modifying these registry keys:

• Navigate to HKEY_USERS\S-1-5-18\Software\GSettings\com\nicesoftware\dcv\display
• Add/modify the value console-session-default-layout with the desired resolution
• Set enable-client-resize to 0 to prevent client-side resolution changes

2. If you have NICE DCV installed (which is common for AWS Windows instances), you can use registry commands like:

reg.exe add HKEY_USERS\S-1-5-18\Software\GSettings\com\nicesoftware\dcv\display /v console-session-default-layout /t REG_SZ /d "[{'w':<1920>, 'h':<1080>, 'x':<0>, 'y': <0>}]" /f
reg add HKEY_USERS\S-1-5-18\Software\GSettings\com\nicesoftware\dcv\display /v enable-client-resize /t REG_DWORD /d 0 /f

(Replace 1920 and 1080 with your desired resolution)

3. After making these changes, restart the instance or the DCV service for the new resolution to take effect.

This issue is specific to the remote access method rather than the Windows Server 2025 version itself. The resolution is typically controlled by the remote access client, and in the absence of a physical monitor, it defaults to a lower resolution.
Sources
Changing my display resolution on my AWS EC2 Windows11 machine | AWS re:Post
AWS EC2 g4dn.xlarge - Parsec 1536x1024 - CRU not working? | AWS re:Post

Yes, we’ve seen this with Windows Server 2025 AMIs.

It’s usually not an AWS networking issue but a display driver / remote session compatibility issue, especially with Bomgar (BeyondTrust). Server 2025 often comes up using the Microsoft Basic Display Adapter, which causes remote tools to get stuck at 800×600.

A few things to check:

• Make sure the latest AWS ENA / EC2 drivers are installed and reboot the instance
• Test with RDP — if RDP shows normal resolution but Bomgar doesn’t, it points to a Bomgar limitation
• In BeyondTrust, avoid console session if possible and enable virtual display / scaling
• Enabling WDDM graphics driver for RDP in Group Policy has also helped in some cases

BeyondTrust support may also be needed, as Server 2025 compatibility still seems incomplete