WDPlugin.dll missing

When i logged into my pc to check on what activity my son had been upto.i got the message WDPlugin.dll missing.I checked his laptop and NSM was still blocking the content it should.I went onto onlinefamily and on home page it was reporting sites that had been blocked but when i went into actvity nothing appears after the message WDPlugin.dll.

running wndows vista

NSM version 1.2.2.2