I've come across an older Zeiss Divari DA variable, its 1.5-6X with a 30mm tube and a 36mm objective.

Clarity is excellent and it would be ideal for what I have in mind but the problem is neither the windage or elevation knobs move. Each knob has 4 screws on top.

Is it just seized or is there some way to adjust it that not immediately obvious.

Can anyone help ?

One of the screws should be located in the center or it should at least be somehow offset from the others. This is the set screw. Release it, turn the dail for adjustment of the reticle and set again when you're done.

McFox, thanks for the tip. The set screw was the one in the middle. However when I removed this screw (completely), the dial would still not turn. I removed the set screw on both dials and neither dial would budge. I somehow suspect the grease in there has set pretty solid.

Any other ideas ?

If it is really hardened grease that's hindering the dials to turn you could try to put the scope into the oven at a moderate temperature. That will soften the grease a bit. Or try a hair dryer.
But eventually you should have the scope refurbished by a service technician.