Sometimes RTV DM will lose track of which columns it should be displaying in the drawing list – eg it sometimes “loses” all the prefix and suffix columns:
If there is a problem with column layouts and filters or the way your RTV Drawing Manager layout is working, you can reset it.
Once you click on Clean Up you get the following dialog box.
It looks a bit scary, but it only affects you, and the layout of RTV on your computer.
Generally you should only clean up your active project.