Hi All, Just in case it's helpful to anybody. This is how I implemented SSO witn NTLM authentication on SLES. I know there is a howto about it on wiki but it was missing few bits in my case. 1) Installed Apache2::AuthenNTLM module by running: # perl -e shell -MCPAN cpan[1]> install Apache2::AuthenNTLM 2) Edited /etc/apache2/httpd.conf and added KeepAlive On 3) Edited /otrs Location in /etc/apache2/conf.d/otrs.conf and added PerlAuthenHandler Apache2::AuthenNTLM AuthType ntlm,basic AuthName Basic require valid-user PerlAddVar ntdomain "DOMAIN dc1 dc2" PerlSetVar defaultdomain DOMAIN PerlSetVar ntlmdebug 0 where: DOMAIN - name of our NT domain (just the first bit of the name, before the first dot) dc1, dc2 - names of our domain controllers (just the hostname, without domain bit). Make sure you can ping those names 4) Edited Config.pm file and added $Self->{'AuthModule'} = 'Kernel::System::Auth::HTTPBasicAuth'; $Self->{'AuthModule::HTTPBasicAuth::Replace'} = 'domain\\'; where domain - name of our domain again 5) Added to /etc/hosts IP_ADDR DOMAIN DOMAIN.CO.UK where IP_ADDR is the IP address of my primary domain controller 6) And the final bit (that took me few hours to work out btw) is to addmod_perlto APACHE_MODULES in /etc/sysconfig/apache2 7) Restart apache and otrs Once this is all done, I'm logged in automatically when going to OTRS login page. The only thing is that it only works when: - I'm using Internet Explorer and the site is in 'Local Intranet' zone - I'm on the local company network, ie. it doesn't work over vpn so it's not perfect. -- Kind Regards, Robert