Upgrading - which one?

[rhowbust]

I currently have a 1.1 beta3 public smf forum. I know this version is really old. I know we should upgarde, but to what?
I tried to upgrade to 1.5 and had a complete disaster when it started looking for tables that didn't exsist.

[xenovanis]

1.1 Beta 3 Public is not really old. It's newer than 1.0.5, that's why you can't 'downgrade' to 1.0.5. You can only upgrade to 1.1 RC1.