Hi, I have an installation that requires to repalce existing version of codec ir50_32.dll in C:\Windows\System32 in Windows Vista with a later version. But the C:\Windows\System32 directory and the file are owned by TrustedInstaller and are protected resources included in windows protected resources scheme. I also understand that TrustedInstaller is not actually a user or a group but a service. The only way I have managed to get it to work is to change the owner on the advanced security settings from TrustedInstaller to an user of a local Administrator group and then replace the file. However, this solution is not suitable for an installation setup. There is an article on msdn http://windowssdk.msdn.microsoft.com/en-us/library/ms734601.aspxthat describes the four supported ways to change windows resource protected (wrp) files or folders. Is there another way for my installation setup to replace ir50_32.dll file? Many thanks, N.

why do you need to change the system file > are you writing a application to use or replace functionality if so look at the MSDN Vista SDK groups