Assuming you are talking about Adagio Payables and not Adagio BankRec, you should never "void" a check, you should "reverse" it. Voiding a check has the same effect as clearing a check, which is to say none, other than removing it from the list of outstanding checks. Reversing a check is what puts the invoice back onto the vendor's account.

You should disable the Void option in Edit | Company Profile | System Options.

If you have posted the Void check, there is no way for you to "unVoid" the check. However, your dealer can do it for you if they have GridView ReadWrite.

Otherwise, you will need to make a journal entry to add the cash back to the GL (credit to the expense), and then re-enter the invoice using a slightly different invoice number.

Steve