Develop CSP in XP

[izyani]

I'm currently done with the source code.

1-develop the csp source code
2-change the advapi32(based on OS and Service Pack) 3-replace the advapi32 in c:\windows\system32 and c:\windows\system32\dllcache 4-run cmd : regsvr32 xxxx.dll 5-test the program

But, in my case, whenever I try to run cmd : regsvr32 xxxx.dll, I will always get the error msg :
DllRegisterServer in xxxx.dll failed. Return code was: 0x80090006.

FYI, I replace all the value for advapi32.dll from the website (change the offset).
I replace the advapi32.dll by following the step:
1-For WIN XP SP3, I replace the advapi32.dll by running in Safe Mode, rename the current advapi32.dll to advapi32.bak, paste the new file there.

Is there anything that I forgot?