This seems to be a common theme and no answer yet.
I too have this problem. I'm on windows server 2003, with Mod_rewrite, mysql, etc.
I have many php applications running without any problems.
I created the database manually, database user manually.
Step 1/ The tables get created and the admin user gets inserted into oc_t_admin.
Step 2/ Have to enter the country into the field (even though I'd like this to be international).
Select 1 country then page just hangs on this step with little flash wheel spinning.
I notice the config.php file is created with correct data in it, so I navigate to root/index.php and I get the message "OSClass isn't installed" with the install button below.
If anyone has figured this out, could you please update/advise here?
Regards
gittin frustrated