Why are there errors when I try to upload a user picture?
All user pictures have a 100x100 pixel image-size limit, and a 100kb file-size limit. If your image exceeds either of those limits, InsaneJournal will not allow you to upload the picture.
Also, one of the more common problems that occurs is that the picture itself is in bitmap format (.BMP), but has been renamed to .GIF, .JPG, or .PNG format. You should try converting the picture to the proper file type.