diff --git a/mutt/templates/Muttrc.local.erb b/mutt/templates/Muttrc.local.erb
index 52499b5..6b70c35 100644
--- a/mutt/templates/Muttrc.local.erb
+++ b/mutt/templates/Muttrc.local.erb
@@ -4,6 +4,9 @@ set use_8bitmime
 set hostname=<%= mail_domain %>
 
 set imap_authenticators="gssapi:plain"
+<% if operatingsystem = "CentOS" and operatingsystemrelease =~ /^6\./-%>
+set ssl_ca_certificates_file="/etc/pki/tls/certs/ca-bundle.crt"
+<% end -%>
 
 set spoolfile=imaps://${USER}@<%= mail_server %>/INBOX
 set folder=imaps://${USER}@<%= mail_server %>