Charles was sent off for a professional foul on Jacques Maghoma during the embarrassing 6-1 thrashing at Burton last time out and will serve a one-match ban.
The Shots were scheduled to play Bradford last weekend but the game fell foul of the weather so Charles must wait to return, with Adam Hinshelwood set to take his place in the centre of defence.
Striker Marvin Morgan and midfielder Kirk Hudson are both struggling with knee injuries and could again miss out, so on-loan Bristol City forward Marlon Jackson will continue to lead the line.
Barnet manager Ian Hendon is confident of having goalkeeper Jake Cole available.
Cole picked up an adductor strain in the closing stages of the 2-1 defeat to Crewe a fortnight ago but is hoping to be fit to start.
Central defender Ismail Yakubu has also been struggling with a thigh problem but could be fit.
Full-back Ryan O'Neill is back from an ankle injury while winger Albert Adomah - who is expected to leave Underhill next month - could also return from an ankle problem of his own.
Joe Devera (thigh), Gary Breen and Clovis Kamdjo (both knee) remain sidelined as Hendon's side look for a win to keep their play-off hopes alive.
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