If you are unable to install iTunes, Skype, Adobe Premiere, or other programs that require a Bonjour service, then you will need to either disable it or remove it. Bonjour is a service also known as zero configuration networking, which enables automatic discovery of computers, devices, and services on Internet protocal networks. I would recommend you uninstall Bonjour or disable it and then try installing iTunes.
You can always reinstall it once you get your iTunes installed. You can also download and install an application to disable bonjour instead.
1. Go to “Start” then “Run” and type a following command without quotes and hit OK.
“%PROGRAMFILES%BonjourmDNSResponder.exe” -remove
2. Browse to a C:\Program Files\Bonjour folder.
3. Rename a mdnsNSP.dll file in that folder to mdnsNSP.old
4. Restart your computer.
5. Delete that Program Files\Bonjour folder
That first command will stop and remove Bonjour Service from your computer. To confirm, go to “Start” then “Run” and type services.msc. Look for a Bonjour service name.
If it’s not there, you’ve successfully removed it. Gizmo Project has created a small tool called TurnOffBonjour, which turns off and removes that Bonjour service. However, it will not remove that Bonjour folder from Program Files.
You will still need to manually delete that Bonjour folder after restarting your computer. A reason why you’re advised to delete that folder after a restart is in case there’s a problem, those Bonjour files are still there for you to restore. If you encountered problems after uninstalling or removing Bonjour, you can easily uninstall and reinstall that service.
These instructions were specifically for Windows XP, but can certainly be tailored for Windows Vista, 7, and 8.