I've had this problem for a long time. If I run a Full System Scan with NIS (current version). My screensaver comes on and when I move my mouse to come out of the screensaver. I find the NIS GUI "frozen". NIS isn't frozen itself just the GUI doesn't show the scan is complete. I have to left click the NIS GUI for it to show the scan is complete. Otherwise it stays frozen looking. I've got the current video card drivers installed for my video card and Windows is up to date.
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