Humphrey, 32, made more than 100 appearances for Preston during his playing days, and also played for Motherwell, Shrewsbury Town, Hibernian and Bury.
He won 12 international caps for Jamaica, and took charge of training at Kendal for the first time on Thursday night.
The Mintcakes had been on the look out for a new manager for the second time this summer, following the resignation of recently appointed Gary Fawcett due to work commitments.
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