Install-ExchangeCertificate -WebSiteName "Exchange Back End" -services "IIS, POP, IMAP" -DomainController $RoleDomainController -InstallInTrustedRootCAIfSelfSigned $true

hi,

i am facing a severe problem during installation of exchange server 2013 on windows2012 standard server.the following massage couldn't go forward,please give me suggestion.

Error:
The following error was generated when "$error.Clear();
          Install-ExchangeCertificate -WebSiteName "Exchange Back End" -services "IIS, POP, IMAP" -DomainController $RoleDomainController -InstallInTrustedRootCAIfSelfSigned $true
          if ($RoleIsDatacenter -ne $true -And $RoleIsPartnerHosted -ne $true)
          {
            Install-AuthCertificate -DomainController $RoleDomainController
          }
        " was run: "Could not grant Network Service access to the certificate with thumbprint 23A7E75AB9E2C0307F8834A36AB947F5CC663ECE because a cryptographic exception was thrown.".