Dll replacements

Hi, I have a couple of problems with my graphics sysytem concerning DLL files.
I would be severely grateful to anyone who could tell me how I can replace current DLL files in my System32 folder.

I have two files in there at the moment that have been labeled as faulty by several applications (failed to load the dynamic library file from D3D9.dll, ect.) and I have replacements for them in a folder on my desktop.

I would like to know how to swap the faulty files for the replacements without the error message 'This file is being used by another person or program'.

I know I have posted a similar request elsewhere on this site but the solution to my other query led me to my current problem. Thanks in advance for any help.

 

Make yourself a BartPE CD and boot up with it. You'll need an XP CD, or have the XP installation files on the harddrive to create one.
http://www.nu2.nu/pebuilder/
With this CD, you'll basically have minimal windows running off a CD, no files will be in use on the harddrive. It has it's own File Explorer, just under the GO button menu where the Start button typically is located.
Personally, I think doing it this way will be a bandaid fix, as your problem may be elsewhere, then again I am not at your keyboard.