Could not retrive the deleted member email

Hi Chief,

My forum had an account with a bad name so I wanted to rename the account. But I could not find out where to do that.

Then I deleted the member in admin functions. Then I tried to create new member with the deleted member's email. But I could not too. Why? The system told me this account was existed and needed log-in. But when I tried to log-in, it told me this was an invalid account.

Help.

PS: I want to re-use the previous account's email.