I have follow below link to install RapidSSL Commercial Certificate on zimbra

Installing a RapidSSL Commercial Certificate - Zimbra :: Wiki

It show below error :

# cd /opt/zimbra/bin
#./zmcertmgr deploycrt comm /tmp/server.crt /tmp/ca_bundle.crt
** Verifying /tmp/server.crt against /opt/zimbra/ssl/zimbra/commercial/commercial.key
XXXXX ERROR: Unmatching certificate (/tmp/server.crt) and private key (/opt/zimbra/ssl/zimbra/commercial/commercial.key) pair.
XXXXX ERROR: provided cert isn't valid.