Full Text Finder links me to the correct journal title, but I can't locate an archive or search box in order to locate the article.
If you got to the publisher/journal page, the article is probably there, but the publisher has a poorly organized site. This occurs most often in freely available titles, such as through DOAJ or EBSCO Open Access titles.
If this is a title with at least medium usage, I can add a note directing the user on how to locate the article or I can temporarily customize the URL so that it at least will go to the archive where the search can be re-executed. I don't like doing that because then it's me who has to manage any changes to that link, but as a temporary measure, I can do it.
The Full Text Finder takes the user to a database vendor log in page.
This is seen occasionally and the reasons are unknown at this time. It's usually an authentication problem and I need to work with the vendor on it when it happens.
Sometimes it's a timing out issue. For example, with EBSCO, if you hang out too long without activity, you'll you see a circular image with their product logos when you try to go back. ProQuest does something similar. The only solution I know of is to close that window and start a new session.