email won't send over wifi

i can send email fine over wifi, but when i send an email i have to turn wifi off before it will send. i dont get an error message or anything, it just says sending at the bottom of the screen with the little circle. the same thing is happening with my ipad. any ideas? ive done everything ive found on the internet but nothing has worked. it is my college's wifi and it worked fine in the spring if that's any help.