Klez.E and any other worm is always very difficult to remove from a network environment. Your IRT (Incident Response Team) needs to react fast and decisive to eliminate the threat. If only one node in your network is infected it can allow a Worm to propagate on even protected machines using the infector's resources never making a function call to the protected machine.

Best bet...If your scared...and you should be....set-up a Honey Pot and look for machines that match the profile and take them out of action.

Provides some useful information on Klez.E

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