unable to post a pic

Hey I all ready have a pic on here and I went to change it. everything was correct. The file size, the size of the picture, and the format where all correct. Can you tell me why It won't let me change the picture? Thank you

Some people have problems changing pics.

You have to log out and log back in to make it change.

Some people say that the change doesn't happen for them for a day or two sometimes. Personally, I've never had to do anything other than log out and back in to see the changed picture.

Make it to where you can have bigger pics than the ones already.