File is not a valid image

[erika_conn]

http://ceconn.com/photo_gallery

At first I noticed it didn't want to upload 5 images so I went to the docs and it was suggested changing it to 1 image.  Sometimes it works, sometimes it doesn't.  I've enabled debug mode for everyone.  Why am I getting the error message below?  All my files are jpg files.

The file you have uploaded is not a valid image !
File: ......./public_html/photo_gallery/db_input.php - Line: 370

[erika_conn]

Never mind.  For now it seemed to have corrected itself.