Problem uploading large file via ftp

I am not able to upload large files via ftp to an application folder on the discountasp.net servers. This file is 260 MB. It takes 30-45 minutes to transfer and then at the end I get an error saying I don't have permission to write to the folder. I see that I have more free disk space than needed for this. But smaller files (a few MBs) upload just fine. I was also able to winzip the file and then upload the compressed file.

Does anyone know what the problem might be? How do you upload large files? And if I have uploaded a compressed file, is there any way to uncompress it on the server?

Thanks,
Kumar