Hey there,

Hopefully you have a more recent recommendation in addition to your previous boss. However, to your question specifically, most schools only accept electronic recommendations anyway. In the event they require paper copies, have it from his current employer. It would be very strange for it to come from the previous company. All s/he has to do is, in the "How do you know the applicant", detail their relationship with you.

In cases like this, the simple answer is almost always the right answer. It would raise so many questions if you start sending recs on letterhead where they person clearly doesn't work.

Bhavik