Reply all message won't send

[redbike]

I received an e-mail message from one of my contacts that was copied to several others not in my contacts. It also contained a small attachment. I tried to "reply all" but the message went to my outbox and would not send and stayed in my outbox for days. Each time I tried to open it I got something to the effect that my reply all message was sending and could not be opened. I finally deleted it from the outbox using the "Airplane Mode" fix, but would like to know why it didn't send. I have a Razr M. Thanks.