''locking this thread as duplicate, please continue at [https://support.mozilla.org/questions/1125639 /questions/1125639]'' Hi. This happened after I updated my Firefox browser.... I can't upload videos to Youtube.... It start to upload, but after 2 sec it says: An error has occurred while sending data over the network. Please check your network connection and try uploading again. I did everything, but nothing happened..... How can I fix this ???? Thanks.