Haynes moved to Meadow Lane in the summer from Sky Bet Championship club Charlton and has made 22 appearances for the Magpies, scoring four goals.
"Danny needs to resurrect his career and both parties have agreed that this will be best at another club," said Notts boss Shaun Derry.
"I'm fully aware of what he possesses as a striker, but sadly it's not working out for him here.
"The door is never closed for Danny and he'll be constantly involved with the first team on a day-to-day basis.
"However, if another club is interested in taking him, we are willing to listen to offers."
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