Symptoms
Parallels Desktop failed to start due to Parallels Dispatcher crash and "Unable to connect to Parallels Desktop" or "Unable to connect to Parallels Service" error is displayed:

Problem appears due to incorrect handling of inconsistent Mac OS X networking configuration.
Resolution
If you are using Firewall or some network filtering software like "Little Snitch" application, please, make sure, that Parallels Desktop is in the list of approved applications.Please, revise the solution from Knowledgebase article below
kb.parallels.com/en/5772
If it does not help, please:
1) Please start terminal (Application -> Utilities -> Terminal) and type the following commands (hit Return after each of them)
sudo cp /Library/Preferences/SystemConfiguration/NetworkInterfaces.plist /Library/Preferences/SystemConfiguration/NetworkInterfacesBackup.plist
sudo rm /Library/Preferences/SystemConfiguration/NetworkInterfaces.plist
sudo cp /Library/Preferences/SystemConfiguration/preferences.plist /Library/Preferences/SystemConfiguration/preferencesBackup.plist
sudo rm /Library/Preferences/SystemConfiguration/preferences.plist
sudo cp /Library/Preferences/SystemConfiguration/preferencesBackup.plist /Library/Preferences/SystemConfiguration/preferences.plist
If the solution did not help and you still receive 'Unable to connect to Parallels Service' error, please check another Knowledgebase article:
http://kb.parallels.com/en/6694