Last updated on March 20, 2025
Rublon MFA for RD Gateway adds Two-Factor Authentication to your Microsoft Remote Desktop Gateway logons.
Installation
My installation fails. What can I do?
First of all, note that you need administrator privileges to successfully install Rublon for RD Gateway.
If you cannot solve your problem, contact us at Rublon Support. Don’t forget to include as much information as you can.
Configuration
Where can I find Rublon MFA for RD Gateway logs?
In case of any problems, we recommend you to look up your log files located in C:\ProgramData\Rublon\RDG\Logs by default. Send both Rublon-RDG.log and Rublon-RDG-Setup.log to Rublon Support along with the description of your problem.
Note that a log file that exceeds 1MB or is older than 24h is archived and a new log file is created. The archived file gets a name that follows the pattern: Rublon-RDG_X-DATE where X is the number of the file and DATE is when the file was archived.
If you cannot find the log files, it may mean that the RDG service does not have access rights to the current log directory. Change the log directory (the logDir parameter in the following Windows Registry: HKEY_LOCAL_MACHINE\SOFTWARE\Rublon\RDG) to a different one, e.g. c:\RDGLogs.
Can I view logs regarding Rublon MFA for RD Gateway in Windows Event Viewer?
Sometimes log files located in C:\ProgramData\Rublon\RDG\Logs are not enough to troubleshoot an issue and you need to look up system logs in Windows Event Viewer. Open Windows Event Viewer and navigate to Application and Services → Microsoft → Windows → Terminal Services-Gateway → Operational/Admin to see events regarding Rublon MFA for RD Gateway.
I am getting Curl error code: 35 in my logs
If you are facing issues with Rublon MFA for RD Gateway and your logs indicate Curl error code: 35, make sure your firewall does not restrict Rublon communication on TCP port 443.
Resizing the window or exiting full-screen mode triggers re-authentication in mRemoteNG
If you are using the mRemoteNG client and resizing the window or exiting full-screen mode triggers re-authentication, set Automatic Resize to No under Appearance in the config panel for the connection.
I’m not getting prompted to authenticate and found MissingFieldException in logs.
If you are not getting prompted to authenticate and find the MissingFieldException in your logs, double-check your application type in the Rublon Admin Console and ensure the values of System token and Secret key in Windows Registry are correct. An application of an incorrect type in Admin Console may produce the following error in logs:additionalInfo: 'Parameter required' exception: 'MissingFieldException'
To check if your application is of the correct type, follow these steps:
1. Log in to Rublon Admin Console.
2. Click Applications on the left.
3. Locate your application associated with RD Gateway and ensure it is of type Remote Desktop Gateway.
4. If your application is of a different type, change the type of your application to Remote Desktop Gateway.
5. Copy and save the values of System token and Secret key.
6. Go to your Windows Registry and locate: HKEY_LOCAL_MACHINE\SOFTWARE\Rublon\RDG.
7. Ensure the values of System token and Secret key in Windows Registry are the same as the values you copied. In case the values differ, replace the old values in Windows Registry with the new values you just copied.
