My sister is trying to join Sylestia, but when she put everything in it says that there is already a user in the location. She is using an email that has not been used before. We live in the same house. I think it thinks that I am trying to make a new account. Is there any way to bypass this so she can use her own sylestia account and not mine?

it's a bit odd that you cannot make another acount with a new e-mail since i have heard of a few players living in the same house who hadn't got any issue with this but it may be a new security system or somthing (apparently it's an old thing, i never noticed it or i just forgot about it lol), contact Krinadon he should be able to help you. ^-^

In order to prevent bot spam, the site doesn't normally allow multiple accounts created from the same IP address. You live together and clearly share an IP which is why it's not allowing her to create an account. The only way around this is to contact the admin, Krinadon. Here is the Contact Us page. You can pm or email him to see what can be done.

Edit: It's actually a very old security thing, Cian. ;)