suddenly, win 7 x64 wont load any wireless usb drivers  

Why did you try to use an usb wifi ? for the speed connection? for the 801 -b/g/n that is not supported by your wifi internal card or to change mac for hacking ? - is a joke . For what you say the problem is the computer or laptop - that must have some good years. Your wifi has an usb 3.0 meanwhile the pc has all the usb working as 2.0. And even if normally nothing happens ,some pc has this problem. I would also think about net discovery if is on and dhcp enabled or disabled- maybe you must setup manual the ip ,the gateway for making the device working. But is not sure that what i say could help.Yesterday i setup a t-link tl 5220g -is a repetition wifi for extern house and i have to setup the dhcp on my lan card.Try also do dissalow your ipv6 from your lan card to see what happens.And the firewall for windows -usualy on the wifi cause problem .I also could give you some command just for try :
netsh int ip reset c: \ Resetlog.txt -riassign all the ip connection,
netsh interface ipv4 reset
netsh interface ipv6 reset
netsh winsock reset
ipconfig /flushdns
and go also to Windows\system32\driver\etc\hosts ,to see if you have some blocked ip.
the file must be like this :
# Copyright (c) 1993-2009 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
# 102.54.94.97 rhino.acme.com # source server
# 38.25.63.10 x.acme.com # x client host

# localhost name resolution is handled within DNS itself.
# 127.0.0.1 localhost
# ::1 localhost

and this is mine ,i don't have no blocked ip

Thank you for replying.

I have the usb wireless because I dont have a wireless card in the desktop...

Perhaps I will buy a pci card to resolve the issue.

It doesnt seem to be an internet problem but an issue with usb drivers somehow.

Too many plugged in and the wireless device and its driver disappears somehow.

Any further thought appreciated

Thanks again
Marc

Hi,

Try to re-install your Windows 7 with Professional or Home Premium.

Given that the OP already has Ultimate installed, how is this supposed to help?

Also, the OP would have to BUY another license, since the version they have is licensed for Ultimate.

This is a very expensive route -- which, when done, is unlikely to solve their problem.

Sorry . It might have problem with the USB wireless.