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I tried the whole day just to import a certificate in Windows XP, but I always failed. I did following:

  1. Create the certificate with a private key (no password):

    makecert -sr LocalMachine -ss My -pe -sky exchange -n "CN=TestCert" -a sha1 -sv TestCert.pvk TestCert.cer
  2. Then put the certificate and private key together into a pfx file:

    pvk2pfx.exe -pvk TestCert.pvk -spc TestCert.cer -pfx TestCert.pfx
  3. Import the pfx file with a command-line tool (German system):

    winhttpcertcfg.exe -I TestCert.pfx -a NT-AUTORITÄT\NETZWERKDInternet ExplorerNST -c LOCAL_MACHINE\My
    Error:  Unable to import contents of PFX file.
        Please make sure the filename and path,
        as well as the password, are correct.

    Filename is OK, and the password was not set. Even if I set the password (e.g. "MyPassword") in Step 1 and type at the end of step 3:

    ... -p MyPassword

I got the same error. Then I tried to import in the certificate console (mmc with certificate snap-in). There I got following error: "Der private Schlüssel, den Sie importieren, erfordert möglicherweise einen Dienstanbieter, der nicht installiert ist." --> "The imported private key may require a service-supplier which is not installed". But the Microsoft Crypto-Service is up and running.

What else can I do?
On Windows Vista and Windows 7, I got this running without these problems.
I need this certificate to run a WCF service.

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1 Answer 1

Meanwhile, I found the reason for the Problem.

Some days before trying to import certificates with private keys, I changed the directory access rights of the location where the private keys are stored. I did following:

cacls "C:\Dokumente und Einstellungen\All Users\Anwendungsdaten\Microsoft\Crypto\RSA\MachineKeys" /E /G "NT-AUTORITÄT\NETZWERKDIENST":R

After that I was no longer able to import certificates containing private keys. As soon as I revoked this particular access right the import of certificates worked well.

I do not understand, why adding an access right will result in practically less access rights.

However, I hope this may help someone of you running into same problem.

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