permission problems

So you noticed that suddenly you don't have access to your files and try stuff like chown or ls -la and you can't figure out what's wrong.  
Don't worry I can help you!

A few Ideas:

- Did you recently make a new user? If yes, check with id username if the uid is the same as the one of your user on the server. You could in that case try reseting the permissions of the share by setting the owner to root in ACL.
- More ideas coming if I continue having problems.