Gt phplist working on 3 domains

I have installations of phplist on three domains. All the links in emails sent out go to a 404 page. all sites are hosted at blue host. I need someone to troubleshoot and solve the issue on all thee domains, it is the exact same problem on all three sites so should be easy when you figure it out to do the additional two sites. I believe the issue to be with the database that assigns a unique url to a user id but im not sure....probably a quick fix im sure.