There is no wpmu 2.8. If you are talking about wpmu trunk then that might be your problem. It’s in the process of getting merged with the 2.8 branch. Things can get goofy in trunk. Try just wpmu 2.7.1.
ups lol.. you’re right Burt.. my mistake.. WPMU 2.7.1
You’re not giving us any specifics.
How are you installing BuddyPress into WPMU?
What is your process?
First things first, do you have WPMU 2.71 running correctly before you try and install BuddyPress?
Secondly, try manually installing BuddyPress by downloading the .ZIP file from the WordPress plugins repository (https://wordpress.org/extend/plugins/buddypress/).
Do not trust the automatic installer! Put the entire contents of the folder in /wp-content/plugins/ and then login to the WPMU admin area’s plugins page and activate.
Let us know what happens.
i’ve did what u say exactly.. it’s already running @ http://www.terminalmusik.com
forgot to inform that i use Nginx.. is it something with the rewrite rules thing?
Looks like your BP site is up and running!
What is your problem again?
Are you saying you can’t access the BuddyPress menus in the WPMU admin area?
ht*tp://example.com/wp-admin/admin.php?page=buddypress/bp-core.php
What happens when you try to go there?
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It could be an issue with RewriteRules if you changed the settings in the .htaccess file…
Yes, u absolutely right!.. i can’t access the Buddypress menus in the WPMU admin area.. it goes blank with notification “No input file specified.” yet the buddypress seems work fine in the frontend..
Many thanks for your concern Ray.. 
