Wiki Software

I installed the wiki software and it all seemed straight forward, I can create and edit a page BUT I cannot get them to display. Either from the wiki page list or the ‘view or preview’ buttons all come back with page 404 error not found. This is on a WPMS install but I’ve already set up two new sites and imported pages which I can view and edit etc so I’m not sure what is wrong – the wiki software looks good. I’ve this site in lock down – it’s a members only so if you need access I’d have to set up an admin account.