There is a link to "Navigator" in the side navigation box. I have been using this feature to quickly access lessons to post and un-post them. (The modules usually take a significant amount of time to load - and if I see the particular module I would like to post and try to post before all modules are fully loaded - the module sometimes does not post, even though it might show green with a check mark. Then I have students contacting me and telling me the lesson has not been posted.) In these cases, I have to go back in to re-post the module.
The matter at hand is this: there are 80 modules currently available for posting in my course. For some reason, I have lost a visual on modules 61-80 in my "Navigator".
Where have they gone and is it possible for them to be re-displayed?