Just configured sendmail for the first time on a Linux RedHat 8.0 (sendmail-8.12.5-7.i386.rpm) When installing Linux RedHat 8.0 I made two accounts: root and administrator After installation I used : [root@fbw root]# useradd Antoni [root@fbw root]# password Antoni When I use: [root@fbw root]# mail -s 'testmail' root test 01 . Cc: --- The message arrives in /var/spool/mail/root --- OK and [root@fbw root]# mail -s 'testmail' administrator test 01 . Cc: --- The message arrives in /var/spool/mail/administrator --- OK but when I use: [root@fbw root]# mail -s 'testmail' Antoni test 01 . Cc: --- The message ends up in /var/spool/mail/root with the following description: Date: Wed, 2 Apr 2003 12:44:48 +0200 From: Mail Delivery Subsystem To: root@fbw.mailserver.nl Subject: Returned mail: see transcript for details The original message was received at Wed, 2 Apr 2003 12:44:47 +0200 from root@localhost ----- The following addresses had permanent fatal errors ----- Antoni (reason: 550 5.1.1 ... User unknown) (expanded from: Antoni) ----- Transcript of session follows ----- ... while talking to localhost.mailserver.nl.: >>> DATA ... User unknown 550 5.1.1 Antoni... User unknown /etc/mail/sendmail.cf dnl include(`/usr/share/sendmail-cf/m4/cf.m4') VERSIONID(`linux setup for Red Hat Linux')dnl OSTYPE(`linux') dnl Uncomment and edit the following line if your mail needs to be sent out dnl through an external mail server: dnl define(`SMART_HOST',`smtp.cablewanadoo.nl') define(`confDEF_USER_ID',``8:12'')dnl undefine(`UUCP_RELAY')dnl undefine(`BITNET_RELAY')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 define(`confDONT_BLAME_SENDMAIL', `GroupWritableDirPathSafe') define(`confDOMAIN_NAME', `$w.mailserver.nl')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 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 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 The '-t' option will retry delivery if e.g. the user runs over his quota. FEATURE(local_procmail,`',`procmail -t -Y -a $h -d $u')dnl FEATURE(`access_db',`hash -T -o /etc/mail/access.db')dnl FEATURE(`blacklist_recipients')dnl EXPOSED_USER(`root')dnl dnl This changes sendmail to only listen on the loopback device 127.0.0.1 dnl and not on any other network devices. Comment this out if you want dnl to accept email over the network. dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA') dnl NOTE: binding both IPv4 and IPv6 daemon to the same port requires dnl a kernel patch dnl DAEMON_OPTIONS(`port=smtp,Addr=::1, Name=MTA-v6, Family=inet6') dnl We strongly recommend to comment this one out if you want to protect dnl yourself from spam. However, the laptop and users on computers that do dnl not have 24x7 DNS do need this. FEATURE(`accept_unresolvable_domains')dnl dnl FEATURE(`relay_based_on_MX')dnl MAILER(smtp)dnl MAILER(procmail)dnl Cwlocalhost.localdomain I browsed the internet for about one day but didn't find any solution to this problem so far. Any suggestions?

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