Users encounter difficulties accessing the Vembu NetworkBackup/OnlineBackup application via the web console on iMac. The web service fails to start automatically even after a successful installation.

The Apache (httpd) service of Vembu NetworkBackup/OnlineBackup client fails to start due to the absence of the required XQuartz (X11) utility. Vembu NetworkBackup/OnlineBackup relies on X11 packages, which are no longer provided by default in OS X.

1. Open the command terminal.

2. Log in as the 'sudo' user.

3. For Networkbackup client, change your working directory to '/Applications/Vembu/VembuNetworkBackup'. For Online Backup client, change it to '/Applications/Vembu/VembuOnlineBackup'.

4. Start the application by invoking the following command:

1. For Networkbackup: `sh startVembuNetworkBackup.sh`
2. For OnlineBackup: `sh startVembuOnlineBackup.sh`
   

5. If you see the error message related to the missing X11 library, the issue is confirmed.

Follow these steps to install the X11 (XQuartz) utility on your iMac:

1. Open a browser and go to the following website: [https://www.xquartz.org/](https://www.xquartz.org/)

2. Click on the latest DMG version download link to install X11.

3. Install the downloaded XQuartz package by following on-screen instructions.

4. After successful installation, restart Vembu NetworkBackup/OnlineBackup from the terminal or using Docker in GUI.

5. You should now be able to access the web console without any issues.