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Welcome to the forums, sonew
In addition to zerotox's suggestion, you might also try a repair of avast.
To do a repair of avast :
For XP -
Control panel > Add/remove programs > click once on avast to select it > click on Change/Remove > scroll down the left pane and click on repair > click OK > follow directions.
For W7 -
Control Panel > Programs > Programs and Features > click on avast > click on Uninstall/Change > click on Repair from the left pane > then follow the steps.
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