Im not totally sure if this is a windows dll,however we can find out by running sfc.
Click Start (windows orb) / All Programs / Accessories / Right click Command Prompt and run as administrator (agree to any UAC prompts).
And enter,note the space between c and /
If windows is preinstalled,sfc should repair any windows dll's,however you may need the windows disc if not preinstalled.
Let sfc run and take its course.If this does not fix your issue come back to us.