Symptoms

Upon Parallels Desktop start the following error message appears:

Unable to connect to Parallels Service. Make sure that the prl_disp_service process is active and it is not blocked by Firewall. For details, please refer to http://kb.parallels.com/en/8089. If the problem persists, contact the Parallels support team for assistance.

Possible Cause

• prl_disp_service is blocked by the firewall
• prl_disp_service cannot start due to insufficient permissions

Resolution

1. Restart the Mac. Try to open Parallels Desktop for Mac again.
2. If it didn't help, launch the Terminal.app (located in Applications > Utilities).

3. Paste the command below into Terminal, then hit Return:

   sudo launchctl stop com.parallels.desktop.launchdaemon
   

4. You may need to type your Mac password and hit Return (you will not see characters while typing)

5. Copy and paste the following command, then hit Return to start Parallels Service:

   sudo launchctl start com.parallels.desktop.launchdaemon
   

6. Try to start Parallels Desktop application or a virtual machine.

If the issue is unresolved...

Uninstall Parallels Desktop and install it again.

Note: your virtual machines will not be affected.