Can anyone tell me why I ALWAYS have a little yellow triangle at the top of my inbox page? I know that means it's having some sort of difficulty, but what? I'm not getting all my emails, and when I do get them it's radomly and not every 30 mins, which is what I've got it set for. How do I fix this? (It's a hotmail account.)

This problem started a couple of weeks ago and nothing I've tried has fixed it, including resetting all the email settings to their original points and a soft reset.