SpamFilter will need the same credentials a user would be using if logging in Windows on the server running SpamFilter. Unless the server is a domain controller, most likely the user will need to specify the domain name along with the username. There is no option to specify a "default domain" to use if the user omits one.

For the rejection problem, are you first of all able to successfully authenticate the user using the "Test" button in the "User Authentication" tab? If yes, then, in SpamFilter, under the "Debug View" tab under Settings, could you please enable the Debug Monitor? You'll need to enter the client IP of the customer attempting to login in the "IP to monitor" field.

This should show the SMTP transactions that the  IP is performing, and could give a clue as to what is happening.

We were already at work yesterday before your last post to add the option for the default domain, as it did make sense :-)

Please see the release note for the latest available build in the reg user area....

// New to VersionNumber = '3.5.4.705';
{TODO -cNew : "Exception occurred during FindMatchInStringList: Invalid pointer operation" errors could cause problems with the reloading of some black / white lists}
{TODO -cNew : Added the logging of the filesize when reloading the black / white list files}
{TODO -cNew : The SURBL blacklist is not being automatically sorted to allow user-defined order}
{TODO -cNew : Added options in [authentication settings] of SpamFilter.ini: ActiveDirectoryAuthAppendDefaultDomain, ActiveDirectoryAuthPrefixDefaultDomain to automatically append or prefix the default domain when authenticating users via SMTP AUTH}


[authentication settings]
;By setting this parameter to 1, SpamFilter will automatically add the Active Directory domain name prefix to the username. For example, if the AD domain is logsat.com, and the username is JohnW, SpamFilter will automatically authenticate the user as logsat.com\JohnW
ActiveDirectoryAuthPrefixDefaultDomain=0

;By setting this parameter to 1, SpamFilter will automatically add the Active Directory domain name suffix to the username. For example, if the AD domain is logsat.com, and the username is JohnW, SpamFilter will automatically authenticate the user as JohnW@logsat.com
ActiveDirectoryAuthAppendDefaultDomain=0

Roberto that worked perfectly, but when I sent an email through, for example to my hotmail account, it forwards that domain onto my email server instead of sending it to a hotmail mx record?

Ok so here's option request #2 :)

Can we have a way to tell spamfilter where to route the "outgoing" mail from authenticated users? Generally most mail servers will be setup to only accept mail for the mailbox's on the server, so any email a user sends will be dropped, if we were able to route the smtp authed email or something along those lines, that would make this work perfectly.