You can export the certificates from most Microsoft programs into PKCS12 format it will have a .pfx extension. Then you can use OpenSSL to convert that to a PEM format. Look at the openssl man page for pkcs12 for more info, on how to do the conversion. -----Original Message----- From: Andrea Gallazzi [mailto:andrea.gallazzi@xxxxxxxx] Sent: Wednesday, March 31, 2010 3:23 PM To: Squid Mailing List Subject: Reverse and SSL cert After little problem I installed squid 3.1.1 with openssl on my ubuntu server 9.10. Now i have my ssl certificate (.cer) on my exchange server but squid (or openssl ?) require a .pem certificate. I have doubts about this. Is the certificate the same of exchange ? (if yes) The same certificate will installed on squid and on exchange? How to make the .pem certificate for squid? thanks -- Andrea Gallazzi http://andreagx.blogspot.com