I've been told that you do not need to plug in the high pressure cut-off switch in order for the compressor to work.

The reason I ask is because I have a new compressor but it has the wrong switch. I was told that it will work without plugging in the switch in the back. Is this true or false?

 

I'm no expert but my impression is that the cutoff needs to be normally closed (connected). Just try it out w/o, it won't harm anything. If it doesn't work then you know you have to short out the plug, exhange it, or make an adapter.