What is mDNSResponder.exe / Bonjour


What is mDNSResponder.exe / Bonjour and How Can


I Uninstall or Remove It? 



You are no doubt reading this article because you’ve noticed the mDNSResponder.exe process 
running in Task Manager, you don’t remember installing it, and it doesn’t show up in the 
programs in Control Panel. So what is it, and how do we get rid of it?


What is mDNSResponder.exe or Bonjour?

The mDNSResponder.exe process belongs to the Bonjour for Windows service, which
is Apple’s “Zero Configuration Networking” application, typically installed 
by iTunes. If you’ve ever wondered how one iTunes install can talk to another on the 
same local network, Bonjour is what actually does this behind the 
Don’t use iTunes? You aren’t alone, and that’s not the only way that Bonjour gets installed
on your computer. It’s also bundled in a whole bunch of other software, like Pidgin, Skype,
and Safari, and used to connect clients together on the same 
It’s implemented as a Windows Service, which you can see if you head into the services panel
(or just type services.msc into the start menu search box). 
You can stop it from here anytime.


The whole problem we have is that it generally doesn’t show up in 
Add / Remove Programs, 
so you can’t get rid of it through any normal methods. Thankfully
you can still 
remove mDNSResponder.exe if you really want to, and it will simply limit some 
of the 
functionality in the apps that might rely on it.

Important: Don’t remove Bonjour if you use iTunes to share libraries, or any other feature
from an application that relies on it.

How Do I Remove It?

First, it should be noted that you can disable Bonjour without necessarily removing it—just head
into the Services panel, double-click on the service, and change the Startup type 
to Disabled.

This is probably your best bet if you don’t really want to break anything—if you have problems you 
can always re-enable it.

Alright, How Do I Really Remove It?

Let’s get down to business. If you’re absolutely sure you want to remove it, it’s really pretty simple.
Open up a command prompt in administrator mode (right-click and choose Run as Administrator),
and then change into the installation directory, usually the following:
\Program Files\Bonjour
If you are using Vista or Windows 7 x64 edition, you’ll need to head into the Program Files (x86) folder instead. Now that you are there, type in the following command to see the options:
mDNSResponder.exe /?

Ah, so now we know what to do to remove it! Simply type in the following:
mDNSResponder.exe –remove
You’ll get a message saying that the service has been removed. (Note again that you need an Administrator mode command prompt)

You’ll want to also disable the DLL file in the directory by renaming it to something else:
ren mdnsNSP.dll mdnsNSP.blah
You should be able to actually remove that entire directory if you really want to.

Wait, How Do I Enable It Again?

Oh, so your favorite application broke? No matter, you can easily re-install the Bonjour service
with the following command:
mDNSResponder.exe -install

But I Deleted It!

See, you really shouldn’t delete things until you are sure they aren’t useful anymore. That’s why renaming is a good thing. Thankfully you can simply head over to Apple’s page and 
install Bonjour again.