Mask problem in after effects

[Jimmy5CB0]

Hi there, I am not able to play with my mask on adobe after effect after updating the program. I am thinking of uninstalling, but I'm concern something might mess up again. Can you or someone assists me on how I can fix this? thanks!

[P.M.B]

Masks need to be applied to layers.  You have no layers.  You don't even have a composition.  

[Jimmy5CB0]

I appreciate the quick reply..The program won't let me apply any even if I have a composition. I get the error msg that's posted on the screenshot.

[P.M.B]

ok, no problem.  i'd say first try purging your cache by menu Edit>Purge>all cache and mem...

I assume you've closed and restarted AE but have you rebooted your system?

Also you can delete your preferences file by holding ctrl-opt-shift while AE is starting up.

You could delete the preference manually too but I dont know where there are on a mac.

Those are the standard things to try first when something weird is happening.