You should only have 1 certificate and it should be a SAN/UCC certificate with the following names in:
owa.domainname.com ( your outkook web access URL)
autodiscover.domainname.com (where domainname.com is the part after the @ in your email address)
servername.domainname.local (the internal FQDN of your server)
but the issue here looks like you have set the OAB to use public folder distribution and there is either something wrong with the public folders or they were not replicated properly.