Hi List, I tried to get two sendmails working together but failed. What did I do wrong? Server A (LAN) is a SuSE 8.0 box with sendmail 8.12.3. It collects mail from the LAN without problems and can deliver them to other servers. If it weren't for SPAM-control of other servers... Server B is a SuSE 7.2 root-server with sendmail-tls (latest patches implemented). This box should become my relay for all mails from the LAN. If I send mail from my kmail-program, I can use authentication methods plain and login without problems. Encryption will be the next step. This is only the technique, I don't use sendmail any mor since years! We have a setup with two Mailservers: A postfix/ B Exchange. A = mail relay gateway and virus scanner B = internal messaging system A collects external mails, sends them to B after virus scanning. B is only for local delivery and uses A as smarthost (B is firewalled, cannot be accessed from external). The headers of mails from B to A are rewritten to come from A. I setup LAN-Server A to relay mail to root-server B (SMARTHOST=...), to use Authentication method PLAIN (SMTP_AUTH_MECHANISMS="PLAIN") and I edited the auth-info file. I double checked correct spelling of servername, username and password. I let SuSEconfig do the dirty job and restarted the server - all corresponding to the article in the SDB. It simply doesn't work here! Regardless of the authentication method, every try ends up with an "authentication failed". I installed a SuSE 8.1 sendmail also but got the same result. To sum it up: kmail -> sendmail-tls works while sendmail -> sendmail-tls does not! Normally - even with sendmail - you don't need any authentification from server A to B! Your internal server only forwards mails and the external server is only a relay server. Hopefully you made backups of the unchanged config files? Configure Server B to forward all mails to Server A (smarthost). Configure Server A to accept all relayed mails from your domain or IP-range or the mailserver B. If possible make a header rewrite of all mails leaving Server A (if your lan is firewalled mails will not come through to Server B except it is in a dmz). This might be done with domain masquerading in sendmail (CM). If you want to get mails from external to internal server change the mailrouting in mailertable. Philippe P.S.: Never let SuSEconfig do work, after you did changes by hand they might get overwritten! Use Yast and SuSEconfig or change things by hand without SuSEconfig!