I'm having the same problem. Only login module showing up and a blank page with the headers and footers showing. Also no access to admin.php after logging in with admin account either.

Fresh install of XOOPS 2.0.5 and set the template_c, cache, uploads folders and mainfile.php with full control (yes, I'm running windows). Running Apache version 2.0.39, PHP 4.2.2, and MySQL 4.0.1 alpha.

Using IE Explorer 6.0.2800.1106IC with Javascript and cookies enabled. One thing different I did was install files into a subdirectory instead of my main web directory, i.e. c:\apache\www\xoops-2.0.5\html instead of c:\apache\www\

Any help would be appreciated.