question about security

let's say i was going to change my internet provider and my provider's email adres if i would do that i cant change my password anymore because my old email adress does'nt exist anymore how would i solve this?

note : this is just a question nothing real

I would try contacting Anet to see if they could do manual change of address and password.

You can just change your email then change yoru password after. There is a screen to do that.

In the character selection screen there is an Edit Account button. You can change your email address and password there. If you change your email address, Anet will send an email to your OLD email address to confirm the change (Part A). They will also send an email to your NEW address (Part B). You will need to confirm the change by clicking on a link in BOTH emails.