the outline in my presentation is blank and I don't know how to fix the problem because the file is compiling without any error. Using MiKTeX editor, here is what the 'code' I am using:
Is this all the code you have? I guess not. Because this piece of code cannot be tested, you probably got no answer yet. A small compilable example (with a test subsection etc.) which shows the problem would improve the chance to get a solution.