Rainer Traut wrote: > Hi, > > sys: Centos 5.2 x86_64 > > Trying to switch from sendmail to postfix I did: > > # yum remove sendmail > > which resulted in erasing of: > mdadm sendmail-doc sendmail sendmail-cf mutt fetchmail redhat-lsb > > I did then: > > yum -y install redhat-lsb.x86_64 postfix > > and got this error: > > Installing: postfix ######################### [1/2] > postfix: fatal: file /etc/postfix/main.cf: parameter setgid_group: > unknown group name: postdrop > warning: group postdrop does not exist - using root > warning: group postdrop does not exist - using root > warning: group postdrop does not exist - using root > warning: group postdrop does not exist - using root > Installing: redhat-lsb ######################### [2/2] > > I checked and indeed there is no group postdrop on the system. > On an El5 system I see the group. > > Thx > Rainer > You don't need to remove sendmail, you can just use system-switch-mail to set postfix as the MTA. There is documentation on setting up a basic postfix server (on CentOS 5) on the Wiki here: http://wiki.centos.org/HowTos/postfix