nimo installation problems

[twistedvincent]

I sucessfully installed the nimo codec pack once,and it installed perfectly, but I had to do a total system recovery and now when I try to install I get the following message:error opening file for writing c:\windows\system32\L3codecp.acm.I get this message more than once and it gives me the option of skipping the step but when I do many of my movies that used to play dont.Any advise would help or suggestions where i coud get all the codecs I need.I just need them to watch movies,nothing complicated.
Thanks