Earlier this week, we received a call from a client stating that they could not longer connect to their Windows device at their office using their personal MacBook. The client was receiving an error message “Unable to Connect” with the error code 0x3000064. This error is related to the latest version of the Windows Remote Desktop application in macOS.
Client using macOS based device receives error 0x3000064 when attempting a remote connection to a Windows 10 computer using the Microsoft Remote Desktop app. It is important to note that the client is using macOS Catalina (10.15.7) and that the remote connection uses a RD Gateway server.
Issue is caused by a faulty update on the Microsoft Remote Desktop app. To solve the issue, client must install a prior version of the Microsoft Remote Desktop app or install the Microsoft Remote Desktop Beta version 10.5.0 (1841).
Please note that some users using the latest macOS Big Sur (11.0.1) have noted that the Beta version of the app does not solve their issue. These users have downgraded to version 10.4.1 (1825) using the link below.
Prior versions of the Microsoft Remote Desktop app and the Beta version 10.5.0 (1841) can be found under Microsoft’s App Center. For prior versions, we suggest to uninstall the current app first before attempting the install of the older app.