So I'm currently trying to upgrade my existing forum system to YAF as it seemed like the best choice for an upgrade. The issue is that I don't want to lose any of the data from the current forum. We have hundereds of users and thousands of posts that I'd like to populate the upgraded forum with, so that it seems active and alive immediately.

The forum posts and such should all be an easy enough job to import, but I'm stuck trying to import the users. As this old forum was custom built, the import users tool doesn't work as we don't have all the necessary data for it to work.

Our users only had a username and password, there's no security question, answer or salt to use. However, I understand that YAF requires users to have a security question and answer. Obviously I cannot make up a single question/answer for every user as they can't be changed by the system later, they'd be stuck with it. I'm a little bit stuck with how to get the old users into the new system.

How would you go about importing all this data?

You can turn off security question/answer via the membership provider settings in the web.config, then you don't have to import that fields

If you don't mind helping me out real quick, I want to import all of these users with hashed passwords and generated salts done through the systems you've got in place, which dlls contain the necessary functions for salt generation and password hashing? Is it YafMembershipProvider that I need to use?