Trying to recover an old email but cannot due to not knowing enough about the contents (due to it being an old account)

I had an email that was hacked and started sending out spam to all my contacts so I decided to just abandon it and make a new one. This was a while ago but I currently need some emails that was stored in that account. The problem I am having is that I don't remember what's in there so I cannot answer enough of the recovery questions. How do I prove it is mine when it's old? The other problem I face (which is very frustrating is that the account that this email sends the password reset to is not active either and is even older itself)