Can you redeposit into an IRA/401k after making a withdrawl?

My girlfriend withdrew money from her retirement account for a downpayment on a house, however the house deal fell through and she had to find a place and was forced in to renting. She says she is not allowed to redeposit the money and will be taxed and penalized heavily. is this true. She did a withdrawl, not a loan against. What can she do to avoid the taxes.