I've generated a certificate using openssl and place it on the client's machine, but when I try to connect to my server using that certificate, I error mentioned in the subject line back from my server. Here's what I've done. 1) I do a test connect using openssl to see what the acceptable client certificate CA names are for my server, I issue this command from my client machine to my server: openssl s_client -connect myupload.mysite.net:443/cgi-bin/posupload.cgi -prexit and part of what I get back is as follow: Acceptable client certificate CA names /C=US/ST=Colorado/L=England/O=Inteliware/OU=Denver Office/CN=Tim Drake/[email protected] /C=US/ST=Colorado/O=Inteliware/OU=Denver Office/CN=myupload.mysite.net/[email protected] 2) Here is what is in the apache configuration file on the server regarding SSL client authentication: SSLCACertificatePath /etc/apache2/certs SSLVerifyClient require SSLVerifyDepth 10 3) I generated a self-signed client certificate called "client.pem" using mypos.pem and mypos.key, so when I run this command: openssl x509 -in client.pem -noout -issuer -subject -serial here is what is returned: issuer= /C=US/ST=Colorado/O=Inteliware/OU=Denver Office/CN=myupload.mysite.net/[email protected] subject= /C=US/ST=Colorado/O=Inteliware/OU=Denver Office/CN=mlR::mlR/[email protected] serial=0E (please note that mypos.pem is in /etc/apache2/certs/ and mypos.key is saved in /etc/apache2/certs/private/) 4) I put client.pem on the client machine, and on the client machine, I run the following command: openssl s_client -connect myupload.mysite.net:443/cgi-bin/posupload.cgi -status -cert client.pem and I get this error: CONNECTED(00000003) OCSP response: no response sent depth=1 /C=US/ST=Colorado/L=England/O=Inteliware/OU=Denver Office/CN=Tim Drake/[email protected] verify error:num=19:self signed certificate in certificate chain verify return:0 574:error:14094418:SSL routines:SSL3_READ_BYTES:tlsv1 alert unknown ca:/SourceCache/OpenSSL098/OpenSSL098-47/src/ssl/s3_pkt.c:1102:SSL alert number 48 574:error:140790E5:SSL routines:SSL23_WRITE:ssl handshake failure:/SourceCache/OpenSSL098/OpenSSL098-47/src/ssl/s23_lib.c:182: I'm really stumped as to what I've done wrong. I've searched quite a bit on this error and what I found is that people are saying the issuing CA of the client's certificate is not trusted by the server, yet when I look at the issuer of my client certificate, it matches to one of the accepted CA returned by my server. Can anyone help, please? Thank you in advance.