Issue

After applying an update or upgrading to another Studio Pro version, the Mendix Service Console fails to start the application. A pop-up error appears with the message:

Request <start> failed: The underlying connection was closed

At the same time, the license settings are grayed out in the Service Console, preventing access to the license manager or the ability to update the license key.

Environment

Applications hosted in On-Premises.

Studio Pro v10.6.9 and older

Studio Pro v10.7.0 - v10.11.0

Cause

This occurs in scenarios where the license has expired, and the runtime refuses to start, leaving the application in an unlicensed and unconfigurable state. As a result, it is not possible to update or replace the license key through the console, leading to the application being stuck in an unlicensed state.

Solution / Workaround

This problem is fixed in specific supported Runtime versions, specifically in 10.6 starting from 10.6.10, and in all versions from 10.12 onward.

To resolve this in the affected Studio Pro versions (if upgrading is not possible), the following workaround can be applied to restore the app’s licensing functionality:

1. Open the app’s Settings.yaml file and locate the value behind QSlotId. It will look similar to this format:
   {47a2f744-ffd9-4ebb-960e-e68fa1add835}.{f196823e-2e95-470f-b3a5-7acf5c98fa6f}

2. Navigate to the folder path on the server:
   C:\ProgramData\Mendix\MDS\{first-part-of-QSlotId}
   and open the file named after the second part of the QSlotId.

3. In that file, remove the entire line that starts with license_key.

4. Save the file.

5. Restart the Mendix application using the Mendix Service Console. The app will now run as an unlicensed app for up to two hours, during which a new license key can be applied.

This workaround restores access to the license settings, allowing a valid license key to be applied and the application to start normally.

Additional information

• Mendix documentation: Activate a Mendix License on Microsoft Windows