When I access my email,no password is necessary even though I set one when setting up account.Does anyone know how I make each attempt to open email password protected?

I think you might have a misconception here - you are using a password to recover your e-mail. It's simply stored when you configured the mail account. If you want to manually enter it every time you go to check your e-mail, you could try clearing the password field in Messaging - Tools - Options - Tap & Hold on the account - configure. But I don't know if it will allow that.

If you're looking to lock down access to your e-mail, it would be better to set a password on your Tilt and have it automatically kick in after a set period.