How to Fix Remote Desktop Error Code 0x204 on Windows and MacOS?

Some users that are trying to connect to a Windows computer from a Mac, Android or a different OS have been getting the Error Code 0x204 when trying to use the Remote Desktop protocol. Although Remote Desktop is a robust tool that allows users to connect to a PC and get their access to apps, files, and network resources, sometimes things aren’t working as they should.

One of the most common problems that will trigger the Error Code 0x204 is an instance in which the Remote Desktop Protocol is not enabled on the Windows machine. In this case, you can fix the issue by enabling it manually via the System Properties screen and by allowing Network Level connections.

However, this can also be caused by your firewall (since the process used by remote desktop is exploited by a lot of malware). In order to fix the issue, in this case, you need to establish an exclusion rule, disable the real-time protection or uninstall the 3rd party security suite altogether.

In some cases, the problem can occur due to some temporary files that are stored inside the Group Containers folder. If this scenario is applicable, you can fix the issue by deleting the UBF8T346G9.com.microsoft.rdc folder.

Method 1: Enable the Remote Desktop Protocol (on the Windows Machine)

One of the most common causes that will cause the Error Code 0x204 when trying to access files from a Windows OS using the Remote Desktop protocol is by far an instance in which the Remote Desktop functionality is not enabled inside the System Properties screen.

This should be your first troubleshooting step if you tried connecting using the Remote Desktop protocol using multiple devices and all of them produced the same issue.

Here’s a step by step guide on ensuring that the Remote Desktop Protocol is enabled on the Windows machine that you which to access files from:

Note: The steps below are universal and should work regardless of the Windows version that you are using on the host machine.

1. Press Windows key + R to open up a Run dialog box. Next, inside the text box, type ‘SystemPropertiesRemote.exe’ and press Enter to open up the System Properties screen.

   

   Note: When you’re prompted by the UAC (User Account Control), click Yes to grant administrative privileges.

2. Once you’re inside the System Properties screen, start by checking if you’re already inside the Remote tab. If you are, go to the Remote Desktop section and change the toggle to Allow remote connections to this computer.

   

   Note: If you are trying to connect to the computer from a different network, you will also need to uncheck the box associated with ‘Allow connections only from computers running Remote Desktop with Network Level Authentication’
   

   

3. Click Apply to save the changes, then attempt to connect using the same Remote Desktop protocol once again and see if the issue is now resolved.

In case the issue is still not resolved, move down to the next potential fix below.

Method 2: Allowing Remote Deskstop through Windows Firewall

Keep in mind that by default, Windows Firewall is not configured to have the Remote Desktop protocol whitelisted.

So if you want to use Remote Desktop to make your files accessible by other machines, you will need to modify the default security settings in order to allow Remote Dekstop and Remote Desktop (Websocket) via the Allowed apps menu of the Windows Firewall settings.

This needs to be done regardless of which Windows version you’re using.

Important: If you’re using a 3rd party firewall suite, the steps below will not apply. In this case, you will need to look for specific steps that will allow you to whitelist the Remote Desktop protocol.

Here’s a quick guide on how to allow the Remote Desktop Protocol to communicate with other devices in this network:

1. Press Windows key + R to open up a Run dialog box. Next, type ‘firewall.cpl’ and press Enter in order to open up the Windows Firewall settings menu.

   

   Note: If you are prompted by the UAC (User Account Control), click Yes to grant administrative privileges.

2. Once you’re inside the Windows Defender Firewall settings, click on Allow an app or feature through Windows Defender Firewall from the left-hand side menu.

   

3. Inside the Allowed apps window, start by clicking on Change settings button (top-right section) in order to be able to modify the list of allowed apps.
4. Scroll down through the list of allowed items and enable the Private & Public box associated with Remote Desktop.

   

5. Next, do the same thing with the entry named Remote Desktop (WebSocket) and press Ok to save the changes.
6. Restart your Windows machine and attempt to connect to it using the Remote Desktop protocol once the next startup sequence is complete.

In case the problem is still not resolved and you’re still encountering the same Error Code 0x204, move down to the next potential fix below.

Method 3: Disabling your 3rd party AV (if applicable)

As it turns out, there are a lot of cases with users that are encountering this issue with 3rd party security suites. McAfee Internet Security is the most common 3rd party suite that is known to facilitate the Error Code 0x204.

What is most likely happening, is the 3rd party AV triggers a false-positive and threats the port used by the Remote Desktop protocol as a malicious attempt to access your files from a distance.

In case this scenario is applicable to your current situation, you should be able to fix the issues imply by disabling the real-time protection of your 3rd party AV suite. But keep in mind that the steps of doing this are specific depending on which AV you’re using.

But in most cases, you will be able to disable the real-time protection (active shields) directly from the taskbar menu. To do this, simply right-click on the taskbar menu icon and look for an option that disables the real-time protection.

In case you’ve done this to no avail or you’re using a 3rd party firewall suite, move down to the next potential fix below.

Method 4: Uninstalling 3rd party Firewall (if applicable)

In case you’re using a 3rd party firewall, disabling it or preventing it from running will not make a difference since the same security suites will remain in place. If the issue is caused by a 3rd party firewall, the only way to fix it is to establish a whitelisting rule that excludes the Remote Desktop from the list of analyzed processes.

But keep in mind that the steps of doing so are very different from tool to tool.

If your AV has no option of adding exceptions, the only viable fix is to uninstall the entire security tool altogether and ensure that there are no remnant files that will still keep that port blocked.

In case you want to follow through with this method, here’s a step by step guide on uninstalling your third party firewall:

1. Press Windows key + R to open up a Run dialog box. Next, type ‘appwiz.cpl’ and press Enter to open up the Programs and Files menu.

   

2. Once you manage to get inside the Programs and Features menu, scroll down through the list of installed applications and locate the entry associated with your 3rd party firewall. When you see it, right-click on it and choose Uninstall from the context menu.

   

3. Inside the uninstallation screen, follow the on-screen prompts to complete the process, then restart your computer.
4. After the next startup is complete, completely uninstall the program to ensure that you’re not leaving behind any remnant files that might still cause this behavior.
5. Once you’ve ensured that your 3rd party firewall is removed, attempt to reconnect using the Remote Desktop protocol and see if the Error Code 0x204 issue has been resolved.

In case the same problem is persisting, move down to the next potential fix below.

Method 5: Using the Remote Assistance invitation

As it turns out, some users have been able to fix the issue by creating an offline invitation using the Windows Remote Assistance utility and opening that on the machine that is unable to connect using the Windows Remote Protocol.

This operation will end up bypassing every potentially blocked port that might be triggering the Error Code 0x204 issue by using an offline invitation.

Here’s a quick guide on how to create this Remote assistance invitation:

1. Press Windows key + R to open up a Run dialog box. Next, type ‘msra.exe’ in the text box and press Enter to open up the Windows Remote Assistance wizard.
    

   

   Note: If you’re prompted by the UAC (User Account Control) prompt, click Yes to grant administrative privileges.

2. Once you’re inside the Windows Remote Assistant wizard, click on Invite someone you trust to help you.

   

3. From the next screen, click on Save this invitation as a file.

   

   Note: You can go for a different option if you find it easier (either attach the invitation with an email program or use Easy Connect)

4. Open the invitation that you previously created on the machine that you’re having trouble connecting with and see if the problem is resolved. Once the invitation is opened, every necessary port should be opened and the Error Code 0x204 should no longer occur.

In case the same problem is still persisting, move down to the next potential fix below.

Method 6: Removing the temp folder of Remote Dekstop (MAC Only)

If none of the methods above have worked and you’re only encountering the issue with OSX, it’s very likely that the temp folder used by the Mac Remote Desktop application contains corrupted files that are preventing the connection from being established.

In case this scenario is applicable to your current situation, you can fix the issue by removing the temp folder from the Group Container’s folder. Here’s a quick guide on how to do this:

1. Ensure the Remote Desktop Program on Mac is completely closed.
2. Click on your Finder icon (bottom-left corner of the screen).

   

3. Inside the Finder app, use the search function to search for ‘group containers‘, then press Return to retrieve the results.

   

4. Once you’re inside the group containers folder, delete the UBF8T346G9.com.microsoft.rdc entry by right-clicking and choosing Move to bin from the context menu.
5. Restart your Mac computer and see if the issue is resolved at the next startup.