fix the error code 0x204

What to do if Remote Desktop Connection for Mac is not working

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The guide below describes solutions for error code: 0x204—an error code that can appear when Mac users attempt to establish a Remote Desktop Mac connection with a Windows PC.

Remote Desktop is a Microsoft program that allows two different operating systems to remotely share. Remote Desktop makes these modern, digital requirements for the work-from-home workforce quite easy, allowing a Mac user/administrator to access Windows and/or mobile devices/servers.

Establishing a remote connection via Mac device (like a Macbook) is as simple as installing the Remote Desktop client (which can be found on the App Store)—then enabling the other machine’s built-in feature.

This remote desktop connection Mac tool opens the door for Mac users to transfer files to other machines that don’t share the same operating system, along with managing programs and apps with maximum fluidity.

While this flexibility is quite the asset, users may find themselves hindered by their Remote Desktop connection for Mac not working with “error code 0x204” on their Mac device (laptops, desktops, or otherwise.)

error code 0x204

It should be noted that this issue most frequently appears while connecting Macs to PCs, and not PCs to PCs.

The most common cause for a Microsoft Remote Desktop not working on Mac (error code 0x204) is often quite simple: the Remote Desktop feature isn’t enabled on the PC computer users are attempting to access.

Establishing a remote desktop connection requires both devices to support the feature… so if one of the devices isn’t running Microsoft’s proprietary protocol, connection failure is a natural consequence.

firewall block

A likely cause for the adverse scenario may have to do with a firewall (be it 3rd-party or native to the operating system.) As a firewall defends your machine against malicious connections, it can simultaneously block remote interoperability as an added precaution.

If (while conducting Remote Desktop connection Mac troubleshooting) the firewall is the culprit, users should whitelist any legitimate connection requests from remote desktops.

In many cases, antivirus software is the cause of the 0x204 Remote Desktop Mac error code. This is especially likely if the antivirus software provides network monitoring configuration features.

Certain antivirus apps could interpret remote connection attempts as unauthorized users with malicious intentions. If that is the case, Microsoft Remote Desktop error code 0x204 is imminent and requires altering the program’s defenses to permit such connections.

When troubleshooting Remote Desktop connection for Mac failures, the most common issue has to do with instances of redundant temporary data created by the RDP client. Deleting any associated folders of the RDP client from the Group Containers directory usually resolves this issue immediately.

All in all, Microsoft Remote Desktop error 0x204 Mac issues have a variety of causes and may require lots of testing to uncover the root problem. The guide below will provide the steps to resolve many of these common causes for error code: 0x204.

How to fix Microsoft Remote Desktop error code 0x204

In the following section, we offer a series of easy methods to resolve the error code: 0x204 when attempting to establish a Remote Desktop Connection with a PC from a Mac device (like an iPhone, iPad or iOS.)

Solution 1: Ensure Remote Desktop is enabled on your PC

Step 1: To open the Run window, hit the Win+R keys while operating the PC you want to connect with.

Step 2: Enter SystemPropertiesRemote.exe (as shown below) then hit Enter.

type systempropertiesremote.exe

Step 3: Select the Remote tab to see if there’s a checkmark beside “Allow Remote Assistance connections to this computer” (as shown below.)

activate remote assistance

Step 4: Hit the Apply button to save changes and exit.

Step 5: Check if error code: 0x204 is still showing on your Mac computer (if so, try the next solution.)

Solution 2: Allow Remote Desktop connections by configuring Windows Firewall

Step 1: On your PC, open the Run dialog using the Win+R key combination.

Step 2: Enter “firewall.cpl” (shown below.)

Step 3: Hit Enter.

type firewall.cpl

Step 4: Click on “Allow an app or feature through Windows Defender Firewall” (located in the sidebar of the Windows Defender Firewall screen.)

transition to allowed apps and features

Step 5: From inside the “Allowed apps and features” section, locate the items “Remote Assistance”, “Remote Desktop”, and “Remote Desktop (WebSocket)”.

Step 6: Ensure the “Private” and “Public” boxes are checked.

Private and Public boxes are checked

Step 7: Hit OK to save changes and exit.

Step 8: Check if error code: 0x204 is fixed ( if it persists, try the solution listed below.)

Solution 3: Create Windows Remote Assistance invitations

Step 1: Open the Run dialog box once again by hitting the Win+R keys on the PC.

Step 2: Enter “msra.exe”.

Step 3: Hit Enter.

type msra.exe

Step 4: Choose “Invite someone you trust to help you” from the Windows Remote Assistant screen (shown below.)

transition to invite someone you trust to help you

Step 5: Hit “Save this invitation as a file” (as shown below.)

Save this invitation as a file

Step 6: Define the save path for the invitation.

Step 7: Click Save.

save path for the invitation

Note: Users should now see a unique password to be used when initiating a remote connection between computers.

remote assistance password

Step 8: To attempt a new remote connection from a Mac to a PC (the error should now be gone—but if it persists, try the next solution.)

Solution 4: Temporarily shut off antivirus protection

For Mac and/or PC users, utilizing 3rd-party antivirus software could hinder a successful remote connection—especially if the antivirus software also provides firewall protection. If that is the case, disabling protection modules may help.

Once disabled, check if error code 0x204 still appears.

Solution 5: Forward port 3389 of Remote Desktop

Double-check to make sure the 3389 port is open from both ends—especially on the Mac side of the connection (Network Utility > Port Scan > Only test ports between 3389 and 3389.)

Alternatively, users may need to configure the router to forward the remote desktop port 3389.

Solution 6: Remove Remote Desktop temp folder from the Mac

Step 1: Hit the Finder icon in the Dock on the Mac machine.

Step 2: Enter “group containers” into the search bar (see below.)

Step 3: Hit Enter (make sure “This Mac” is selected rather than a specific directory within the search settings area.)

find group containers

Step 4: Find and open the Group Containers folder.

open group containers folder

Step 5: Located the “UBF8T346G9.com.microsoft.rdc” folder and right-click it.

Step 6: Choose “Move to Trash” from the context menu.

delete UBF8T346G9.com.microsoft.rdc folder

Step 7: Restart your Mac then see if the Remote Desktop error code 0x204 is resolved.

Final thoughts on (RDC) Remote Desktop Connection Mac command line error code: 0x204

If none of the solutions outlined above solve the error, then users should attempt to reinstall the Remote Desktop client on the Mac. Very likely, reinstalling the client won’t be required.

Usually, the hardest aspect of fixing error code: 0x204 on Mac has to do with an issue from the PC end of the connection. Be sure to test out the variety of methods shared above, which should (hopefully) allow you to enjoy the Remote Desktop feature between your Mac and PC.