No, don't reboot as it doesn't require it. End task on it via Task Manager.
Delete that combofix.exe from your desktop and
download a fresh copy, then run the ComboFix /u again.
Please let me know if it successfully uninstalled.
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Member of ASAP since 2005
Member of UNITE since 2006
"It is one life whether we spend it laughing or weeping." "Take the time to laugh--it is the music of the soul."