I found a couple of discussions about this here;
http://answers.microsoft.com/en-us/windows/forum/windows_7-windows_update/usb-ports-not-working-after-sp1/624fcafc-5f5b-e011-8dfc-68b599b31bf5
which leads on to this one;
http://social.technet.microsoft.com/Forums/en-US/w7itproperf/thread/f3cc956d-3b75-4b93-b4e1-61a3ffd7573c/
See if they help.
Mark
I have a Lenovo Win7 PC. USB ports were working fine, until SP1 upgrade. Now cannot get USB to work at all. Uninstall doesn't fix. Rollback to before SP1 doesn't fix. Help!

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