Objects converted to symbols not showing up in workspace

After restarting the program, rebooting, and even reinstalling multiple times, this problem still arises. All of the objects I’ve turned into movie clips, or buttons just disappear. They still work in the published movies, but are invisible in the main timeline. I don’t understand the problem. I’ve started new files to make sure it isn’t my movie that is corrupt, but the second they turn into symbols, they disappear. Is there a solution to this that i’m overlooking?