PROBLEM..

I am unable to upload my final video. It has been on my computer for about a month and when i went to upload it yesterday it to here it kept saying 'sorry there has been a problem unable to upload' so i went to change it to a you tube video and it said it was gonna take 375 minutes. I did it but there was an error when uploading and there is no sound and also when i go to upload from my you tube videos it can not be located. I was wondering if you have already seen it on the Macs at school that you will be able to mark it from there? I spoke to Mrs Watkin and she said that should be ok?