Your last two posts really made me hopeful to solve my issue, but unfortunately it didn`t.
I followed the instruction of multisite module and point my traffic of test.myseconddomain.com to
mymaindomain.com/testarea/processwire.
on mymaindomain.com/testarea/processwire/test.myseconddomain.com I can reach the page.
on test.myseconddomain.com I land on the level of mymaindomain.com (basic example site) of my installation.
I am using password protection for the hidden testarea in .htaccess. I also tested if this causes problems, but it does not work either way. Also I tried to put test.myseconddomain.com into the $config->httpHosts = array()
but then I get 404.
what is the best structure for one install with one database and several different domains and one hidden testarea?
my PW install now is in this testarea...
thank you so much for your help!