Restoring the magnetic-flux of a magnet

[cockrobin]

How do you go about restoring the magnetic-flux of a horseshoe magnet that has lost all its' magnetic-flux? The magnet was originally weak and was sent to a company to have the magnetisim restored and when returned, all magnetic-flux was gone, as if it had been degaussed.

 

[Antiphon]

They demagnetized it instead of remagnetized it.

It needs to have a keeper plate on it after being remangetized.

 

[cockrobin]

Thankyou for the information. What source is there for remagnitizing a magent? The horseshoe magnet measures 2 3/4" H X 2 1/2" W X 1" X 3/8" thick.