Couple of reasons:
Either you entered that statement with the double quotes at beginning/end (which is wrong, leave them off)
or you didn't put the VrayBridge.key inside the CINEMA 4D R11.5 folder. Or your CINEMA 4D installation is a different version.
Here's the terminal commands for the the default install locations for CINEMA 4D versions 10 to 11.5
CINEMA 4D R10: sudo chmod 755 "/Applications/MAXON/CINEMA 4D R10/VrayBridge.key"
CINEMA 4D R11: sudo chmod 755 "/Applications/MAXON/CINEMA 4D R11/VrayBridge.key"
CINEMA 4D R11.5: sudo chmod 755 "/Applications/MAXON/CINEMA 4D R11.5/VrayBridge.key"
With those statements you need to leave the double quotes in (e.g. enter line for your CINEMA version exactly as shown).
If your CINEMA installation is at a custom installation path you need to adjust the path inside the double quotes accordingly.
And if you saved the VrayBridge.key file from the XF keygen somewhere else
than inside your CINEMA 4D installation, what you can then do is try the following:
- Open Terminal.app
- At Terminal prompt type:
sudo chmod 755
- Type a space after the 755
- Switch to Finder where you saved the VrayBridge.key
- Drag the key file from the Finder onto the Terminal window so that the insertion cursor appears after the space you typed in step 3
Terminal will then auto-fill the correct path to the key file which will make the Terminal command complete and ready to execute
- Terminal should be the active app after the drag operation, if it isn't switch to Terminal. Then press enter.
- Enter your admin pass when prompted (it will not show up when entered)
- Press return
With these steps you corrected the permissions bits for the key file and all that's left to do
is to put the corrected VrayBridge.key file in the same folder as your CINEMA 4D.app.
Hope this helps.