I had the same problem when trying to d/load it using IE (internet explorer) In the end I d/loaded it using google chrome. give that a go and see how you get on. Obviously this will only be any help to you if you have chrome installed?
Close all programs, delete old version then try again. My system is Windows XP (32 bit), Internet Explorer 8.
What is your operating system & version?
What is your web browser?
What exactly means "can not"?
P.S. please do not post in all-caps; very difficult to read!