Update your permalink settings and user pretty urls. No need to mess with .htaccess. Just use a custom structure like:
/%category%/%postname%/
And press save.. done 
Allready tried that aswell.
Just tried it again but still no effect. any other tips?
Deactivate BuddyPress and BP plugins and change to default twentyten. Permalinks should be resolved before installing BP.
Have you searched online for ISAPI rewrite and WordPress? This looks like the ticket http://www.helicontech.com/cms_articles/wordpress.htm or you could post in their forums.
WP Codex has some info for IIS servers https://codex.wordpress.org/User:ringmaster/IIS#Configuring_Permalinks
Just tried it all but still no effect.
Anyone got another solution next to posting it into their forums?
Little update!
It seems like the buddypress links like : activity & members forget to use /index.php/ before of their links.
when i type it before it they simply work.
http://platform.wpbase.nl/index.php/members <– works
But by default it links to http://platform.wpbase.nl/members
How can i fix this?
Why do you have your permalinks setup in this fashion? Do you use Nginx as a server or something else which makes it harder to use “regular” permalinks? The /index.php/ part in your url is not needed, and causes the problem. Have you put this in your wp-config file or something?
It’s a windows (iis) server and the index.php is a default wordpress functionality.
Just look at the permalink structure of wordpress and you’ll see it!
but still the problem isn’t resolved…
So anyone any tips?
