In the light of recent attacks the CA’s has recommended that resellers should no longer provide the service of supplying certificates as PFX-files.
PFX-files include both the public and the private key and to many customers it has been simple to order a certificate as a PFX-file in order not to have to go through the CSR-file generation. This however has turned out to be a risky practice. The business has now recommended that suppliers should not provide this service anymore.
Hence ExpertSSL has now removed this from the portfolio.