It depends on what internet download manager is being used. Each download manager has different way of deleting history.
windos7 is a operating system. without windos7 operating system the compuer can not work. windos 7 is the operating sytem that gives to program to run. all the program that can be created by the windos 7 like animation, vlc, movies , images etc.
It depends on the basis under which the question is asked. In many cases, this message comes up because the copy of Windows used is actually not genuine. Tampering with this is crime and WikiAnswers does not provide information that will aid or support criminal activity. If the message is incorrect, i.e. the copy of Windows used actually is genuine, this message is likely occuring because of a virus on the computer or some aspect of the System Registry being missing. Either way, it should be examined by a trained professional.
You have to have 1MB Of RAM and for home premium you need 16 GB Of Disk Space and for Professional and Ultimate you need 20 GB Of Disk Space. Then backup your files on a external drive and then upgrade it. So if you have a Compaq like me and it says 512 or something technically you can't. For Hard Drive I would have you have a 500 GB Drive Or Something because I have a IBM and the Hard Drive I found was 2GBS And You Can't Put Much On It :)