MSVCRIT.DLL error

Hi, I have NT 4.0 Server (SP6), IIS 4.0 & Oracle 8i & Enterprise Manager with Database on P-III@833MHz, 256MB Ram, 10GB IDE HDD. The Database is working fine on it & when I install Oracle Application Server 9i (HTTP Server) it gives e error as “Error in writing to C: Drive – “\WinNT\System32\Msvcirt.DLL”. Let me know how to solve this ASAP.
Akash