I've set up a server with postfix for sending mails. However, when I try to send an email to a gmail account, I get the following errors:
May 16 23:41:47 vps4195 postfix/smtp: certificate verification failed for gmail-smtp-in.l.google.com: num=20:unable to get local issuer certificate May 16 23:41:47 vps4195 postfix/smtp: certificate verification failed for gmail-smtp-in.l.google.com: num=27:certificate not trusted
After these errors the mail is delivered to the gmail accounts, but the mail will almost always go to the spam directory, even when no mail filter is used inside gmail.
So how can I get rid of these errors?
ps. Probably this isn't enough information for you to help me fix this, but I'm not really an expert on this subject, so please tell me if I need to post more information.
edit: The system postfix is running on is CentOS 5.5 (VPS)