Can't upload personalized picture

When I edit the personalized picture and try to upload a new personalized picture, I get this error msg :

“The attachments upload directory is not writable. Your attachment or avatar cannot be saved.”

How to change my personalized picture ?

@FriendlyFire:

Best bet is to go on imageshack.us or photobucket.com and plug it there, and use the link to that image on the forums here.

Thanks for your reply.

You mean that, the personalized picture upload function can’'t be use like before ?