The issue

After a recent Windows security update, some users started seeing a new Remote Desktop Connection security warning when opening saved .rdp files or launching RDP shortcuts.

The message usually says:

“Caution: Unknown remote connection”

It may also show details such as:

• Publisher: Unknown publisher
• Type: Remote Desktop Connection
• Remote computer: server name or IP address
• Options for redirected resources like Clipboard, Printers, Smart cards, or WebAuthn

Microsoft introduced this new Remote Desktop security dialog to help protect users from potentially malicious .rdp files, which can be abused in phishing scenarios or used to redirect local resources to a remote computer. Microsoft documents this behavior in its Remote Desktop security warning guidance.

For many IT administrators, however, this warning can become annoying in controlled environments where RDP files are used daily and the remote servers are known and trusted.

Why does this happen?

The new dialog appears because Windows now treats unknown or unsigned RDP connection files more cautiously. The warning is especially visible when a saved .rdp file includes local resource redirection settings, such as clipboard or printer redirection.

By default, newer Windows Remote Desktop clients use the newer security warning dialog. Microsoft documents the RedirectionWarningDialogVersion setting and notes that the default value is 2, which shows the newer dialog introduced with the April 2026 security update. Setting it to 1 restores the previous dialog behavior.

Temporary workaround: restore the old RDP warning behavior

To restore the previous Remote Desktop warning behavior, open Command Prompt as Administrator and run:

reg add „HKLM\Software\Policies\Microsoft\Windows NT\Terminal Services\Client” /v RedirectionWarningDialogVersion /t REG_DWORD /d 1 /f

After running the command, close all Remote Desktop windows and start the RDP connection again.

This creates the following registry value:

Microsoft also documents this registry value as a way to revert to the previous dialog behavior if the new update causes temporary disruptions in an environment.

How to restore the default Windows behavior

If you want to undo the change and return to the default new Remote Desktop security warning, run this command as Administrator:

reg delete „HKLM\Software\Policies\Microsoft\Windows NT\Terminal Services\Client” /v RedirectionWarningDialogVersion /f

This removes the custom policy value. Once removed, Windows will return to its default behavior, which is the newer Remote Desktop security dialog.

Important security note

This registry change should be treated as a temporary workaround, not a permanent security solution. Microsoft warns that support for this setting may be removed in a future Windows update, so organizations should plan to adapt to the new security model rather than rely on this registry value forever.

For business environments, the better long-term solution is to properly manage and sign trusted .rdp files, or distribute Remote Desktop settings through controlled administrative tools such as Group Policy.

Recommended usage

Use this workaround only when:

• You manage the computer or the environment.
• You trust the RDP destination.
• The RDP file comes from a known internal source.
• You understand that redirected resources like clipboard and printers can expose local data to the remote machine.

Do not disable or bypass warnings for unknown .rdp files received by email, downloaded from the internet, or sent by untrusted sources.

Summary

The new Windows Remote Desktop warning is a security improvement designed to protect users from risky or malicious RDP files. However, in trusted IT environments, it may interrupt normal workflows.