unipolar everything is shorted?

Probably... You don't give enough of a description to really be sure. However unipolar steppers, in most cases, will have four windings, which all have to be connected to the 'common' rail at one end. The commonest configuration (actually designed so the motor can also be used in bipola mode), is two 'pairs' of windings, each with a centre tap, and these taps are connected together. The other end of each winding, then goes to the four driver sources. The resistance of each winding may be quite low (anything from perhaps 200R, on a 'small' motor, down to possiblty 1.5R, on larger motors. Most normal 'continuity testers', will see resistances at the lower end of this, as a 'short'. You need to identify the type of motor, and then get the data sheet, to see how the connections are done.

Best Wishes