Postfix and Sendmail

Thank you in advance!

Hi,
I have installed Sendmail and Openwebmail on RedHat 9. I am also using IMAPS to log on and download my mail. I am using SSL on the web to use Openwebmail. I have a registered domain. I am currently hosting it at my business. I have DNS installed. I have an MX record pointing to my mailserver. When I use "DIG" or "NSLOOKUP" I get an appropriate response. I have configured my hosts file. I have configured sendmail using sendmail.mc and NOT sendmail.cf. I have run m4 after making changes. I believe my problem is with "relay". I also have a side question when editing the sendmail.mc file. If you comment out by removing the " # " character, should you also leave the dnl at the beginning and the end as not to create a line space? Example:
dnl # DaemonPortOptions=Port=smtp, Name=MTA dnl ( I assume this is comment out and not parsed)
dnl DaemonPortOptions=Port=smtp, Name=MTA dnl (This is uncommented out and parsed?)
or is this correct?
DaemonPortOptions=Port=smtp, Name=MTA dnl (dnl at the end only)
or this?
DaemonPortOptions=Port=smtp, Name=MTA     (No dnl at end or beginning)

The major PROBLEM:

I can send mail from Outlook or Webmail using https: both on my network and remotely to users only on my domain. I can't send e-mail via sendmail to anyone who is not part or my domain. I receive the following error almost exclusively:

The message could not be sent because one of the recipients was rejected by the server. The rejected e-mail address was 'randol.larson@emcmail.maricopa.edu'. Subject 'Again', Account: 'mail.larsonlinux.org', Server: 'mail.larsonlinux.org', Protocol: SMTP, Server Response: '550 5.7.1 <randol.larson@emcmail.maricopa.edu>... Relaying denied', Port: 25, Secure(SSL): No, Server Error: 550, Error Number: 0x800CCC79

I have open on my firewall the following: 25 53 80 443 and 993. I have tried "providing a username and password to outgoing mail to authenticate. I am pretty sure it is in "relaying" the mail, and I have tried several suggestions from postings here. I can telnet to port 25 as the instructions explain. I have read the relaying is turned off or tweaked to prevent others from using you as SPAM in a can.

I will copy my sendmail.mc file (I have taken out some of the comments because of size of posting here. Should I drop sendmail and try Postfix, can I do that after configuring sendmail. Any help you can give will be surely appreciated. Again, thank you. Christy Jo

divert(-1)dnl
dnl #     make -C /etc/mail
include(`/usr/share/sendmail-cf/m4/cf.m4')dnl
VERSIONID(`setup for Red Hat Linux')dnl
OSTYPE(`linux')dnl
define(`SMART_HOST',`smtp.mail.larsonlinux.org')
define(`confDEF_USER_ID',``8:12'')dnl
dnl define(`confAUTO_REBUILD')dnl
define(`confTO_CONNECT', `1m')dnl
define(`confTRY_NULL_MX_LIST',true)dnl
define(`confDONT_PROBE_INTERFACES',true)dnl
define(`PROCMAIL_MAILER_PATH',`/usr/bin/procmail')dnl
define(`ALIAS_FILE', `/etc/aliases')dnl
dnl define(`STATUS_FILE', `/etc/mail/statistics')dnl
define(`UUCP_MAILER_MAX', `2000000')dnl
define(`confUSERDB_SPEC', `/etc/mail/userdb.db')dnl
define(`confPRIVACY_FLAGS', `authwarnings,novrfy,noexpn,restrictqrun')dnl
define(`confAUTH_OPTIONS', `A')dnl
dnl #
dnl define(`confAUTH_OPTIONS', `A p')dnl
dnl #
dnl TRUST_AUTH_MECH(`EXTERNAL DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
dnl define(`confAUTH_MECHANISMS', `EXTERNAL GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
dnl #
dnl # Rudimentary information on creating certificates for sendmail TLS:
dnl #     make -C /usr/share/ssl/certs usage
dnl #
dnl define(`confCACERT_PATH',`/usr/share/ssl/certs')
dnl define(`confCACERT',`/usr/share/ssl/certs/ca-bundle.crt')
dnl define(`confSERVER_CERT',`/usr/share/ssl/certs/sendmail.pem')
dnl define(`confSERVER_KEY',`/usr/share/ssl/certs/sendmail.pem')
dnl #
dnl # This allows sendmail to use a keyfile that is shared with OpenLDAP's
dnl # slapd, which requires the file to be readble by group ldap
dnl #
dnl define(`confDONT_BLAME_SENDMAIL',`groupreadablekeyfile')dnl
dnl #
dnl define(`confTO_QUEUEWARN', `4h')dnl
dnl define(`confTO_QUEUERETURN', `5d')dnl
dnl define(`confQUEUE_LA', `12')dnl
dnl define(`confREFUSE_LA', `18')dnl
define(`confTO_IDENT', `0')dnl
dnl FEATURE(delay_checks)dnl
FEATURE(`no_default_msa',`dnl')dnl
FEATURE(`smrsh',`/usr/sbin/smrsh')dnl
FEATURE(`mailertable',`hash -o /etc/mail/mailertable.db')dnl
FEATURE(`virtusertable',`hash -o /etc/mail/virtusertable.db')dnl
FEATURE(redirect)dnl
FEATURE(always_add_domain)dnl
FEATURE(use_cw_file)dnl
FEATURE(use_ct_file)dnl
dnl #
dnl # The -t option will retry delivery if e.g. the user runs over his quota.
dnl #
FEATURE(local_procmail,`',`procmail -t -Y -a $h -d $u')dnl
FEATURE(`access_db',`hash -T<TMPF> -o /etc/mail/access.db')dnl
FEATURE(`blacklist_recipients')dnl
EXPOSED_USER(`root')dnl
dnl #
dnl # The following causes sendmail to only listen on the IPv4 loopback address
dnl # 127.0.0.1 and not on any other network devices. Remove the loopback
dnl # address restriction to accept email from the internet or intranet.
dnl #
dnl # DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
DaemonPortOptions=Port=smtp, Name=MTA dnl
dnl #
dnl # The following causes sendmail to additionally listen to port 587 for
dnl # mail from MUAs that authenticate. Roaming users who can't reach their
dnl # preferred sendmail daemon due to port 25 being blocked or redirected find
dnl # this useful.
dnl #
dnl DAEMON_OPTIONS(`Port=submission, Name=MSA, M=Ea')dnl
dnl #
dnl # The following causes sendmail to additionally listen to port 465, but
dnl # starting immediately in TLS mode upon connecting. Port 25 or 587 followed
dnl # by STARTTLS is preferred, but roaming clients using Outlook Express can't
dnl # do STARTTLS on ports other than 25. Mozilla Mail can ONLY use STARTTLS
dnl # and doesn't support the deprecated smtps; Evolution <1.1.1 uses smtps
dnl # when SSL is enabled-- STARTTLS support is available in version 1.1.1.
dnl #
dnl # For this to work your OpenSSL certificates must be configured.
dnl #
dnl DAEMON_OPTIONS(`Port=smtps, Name=TLSMTA, M=s')dnl
dnl #
dnl # The following causes sendmail to additionally listen on the IPv6 loopback
dnl # device. Remove the loopback address restriction listen to the network.
dnl #
dnl # NOTE: binding both IPv4 and IPv6 daemon to the same port requires
dnl #       a kernel patch
dnl #
dnl DAEMON_OPTIONS(`port=smtp,Addr=::1, Name=MTA-v6, Family=inet6')dnl
dnl #
dnl # We strongly recommend not accepting unresolvable domains if you want to
dnl # protect yourself from spam. However, the laptop and users on computers
dnl # that do not have 24x7 DNS do need this.
dnl #
FEATURE(`accept_unresolvable_domains')dnl
dnl #
FEATURE(`relay_based_on_MX')dnl
dnl #
dnl # Also accept email sent to "localhost.localdomain" as local email.
dnl #
LOCAL_DOMAIN(`localhost.localdomain')dnl
dnl #
dnl # The following example makes mail from this host and any additional
dnl # specified domains appear to be sent from mydomain.com
dnl #
dnl MASQUERADE_AS(`mydomain.com')dnl
dnl #
dnl # masquerade not just the headers, but the envelope as well
dnl #
dnl FEATURE(masquerade_envelope)dnl
dnl #
dnl # masquerade not just @mydomainalias.com, but @*.mydomainalias.com as well
dnl #
dnl FEATURE(masquerade_entire_domain)dnl
dnl #
dnl MASQUERADE_DOMAIN(localhost)dnl
dnl MASQUERADE_DOMAIN(localhost.localdomain)dnl
dnl MASQUERADE_DOMAIN(larsonlinux.org)dnl
dnl MASQUERADE_DOMAIN(mydomain.lan)dnl
FEATURE(always_add_domain)dnl
FEATURE(`masquerade_entire_domain')dnl
dnl FEATURE(`masquerade_envelop')dnl
MASQUERADE_AS(`larsonlinux.org')dnl
MASQUERADE_DOMAIN(`larsonlinux.org')dnl
MASQUERADE_AS(larsonlinux.org)dnl
MAILER(smtp)dnl
MAILER(procmail)dnl