Marc Sherman wrote: > Robert Cates wrote:
>
>> OK, here they are (one of the differences is the @kormar.net (from
>> Outlook)
>> and @kormar.de (from Thunderbird) addresses, but I don't see where that
>> could matter)...
>
>
> I'll bet that's it, in fact. Try reconfiguring your outlook account to
> send as kormar.de, and vice-versa, and see what happens.
It's SPF. kormar.net has an SPF record, kormar.de does not.
I'd eliminate the kormar.net SPF record, if I were you.
