MyBB Community Forums

Like the title says.

I want to reinstall mybb 1.4.4 from scratch, but I don't want to loose my members or post.

How do I do this?

Well by definition, installing is when all new tables are created with default data. If you make a backup you can import that after, but then that would defeat the point of installing, so if you can tell us why you want to reinstall, we might be able to help you better.

my website has a lot of corrupted pages.

That is for the reason I'm reinstallation mybb

... will reinstalling MyBB fix a page on your website?? How do you know what it requires re-installation?? Because if you want to keep your users, you'll need a backup, which means you'll go back to how your forums are now anyway.

Here are the problems:

Users can't Register (Blank Page)
Can't activate and deactivate plugins in Admin CP
Languages shows blank pages in Admin CP
Can't change users info.
Sometimes Admin CP looks wierd.

I don't think reinstalling will solve any of that to be honest. Try re-uploading files first.