Restarting of tableau server will fix this error, Its due to search and indexing problem i guess. check the article below:
We've tried that a number of times now, and when we check the processes they're all running fine.
Like i said in the original post we have a few users who are able to view content but most can't. Also a number of the ones who could now are experiencing the same issue.
I did discover this article yesterday, but it says its only for v8.1?
I request you to raise a ticket to tableau support. They can investigate the log files and can tell you the solution.In my most of the cases tableau server restart need to solve the problem but in your case its not happening.