I'm trying to get Network Link Conditioner working on my machine that is running OS X Mavericks. I'm running Developer Preview 8 (the latest as of this writing). I downloaded the "Hardware IO Tools for Xcode 5 Developer Preview - June 2013" to get the Network Link Conditioner pref pane. I have also tried the version of Network Link Conditioner from the previous Hardware IO Tools bundle which fails to open with a "Could not load Network Link Conditioner preference pane." error when trying to load it.
With the version for Xcode 5 I get one of two fail states.
First, when I open NLC and click the lock icon to "make changes" I see the administrator unlock window that says:
com.apple.Network-Link-Conditioner.remoteservice.xcp wants to make changes. Type your password to allow this.
When this shows up I am unable to enter my password. No keyboard characters are registered in the password field, or in any other application until I cancel the password prompt. I have no trouble with the equivalent dialog in any other preference panes.
Second, I am sort of able to get past the password issue by uninstalling the latest NLC pref pane, installing the previous version, uninstalling the previous version, and then re-installing the latest NLC preference pane. However, I note that the password dialog is different in this case. I get the more generic:
System Preferences wants to make changes. Type your password to allow this.
In this second failed state, once I type in my password the NLC pref pane is fully accessible but has zero affect on my network link.
Has anyone been able to use the Network Link Conditioner successfully on OS X Mavericks?
Update:
The version of Hardware IO Tools released on October 22 and the final release of Mavericks appear to be working excellent.
I was also having problems with Network Link Conditioner working after upgrading to Mavericks. For me the problem was the default security settings after the upgrade that prevented software from running unless it came form the Mac App Store.
Updating this setting:
System Settings > Security & Privacy > General > Allow apps downloaded from: > Anywhere
and reinstalling the Network Link Conditioner pref pane fixed it for me. Without this setting you can install and enable it, but it has no effect and silently fails.
How I got it solved was:
It should be working fine now!
On macOS Sierra v10.12.1 with Xcode 8.1, I tried a couple of the Hardware IO Tools for Xcode downloads. All of which resulted in a silent failure like @aidaan such that the Network Link Conditioner plain didn't do anything.
After finding this discussion, I uninstalled the previous Hardware IO Tools for Xcode components, and instead utilized the Additional Tools for Xcode 8.1 downloaded from the downloads page, the Network Link Conditioner in the Hardware directory for that .dmg worked perfectly.
Try re-installing it. It fixed the issue for me, though I was having different error messages.
Open System Preferences, right-click (or control-click) on the Network Link Conditioner and click "Remove Network Link Conditioner" to remove it.
In Xcode got to the Xcode menu -> Open Developer Tool -> More Developer Tools...
In the browser window that opens, grab the most recent Hardware IO tools .dmg
Double click the "Network Link Conditioner.prefPane" on the disk image to install it.