BuddyPress.org

I am experiencing the same issue, and it seems like it is less about which plug in, and more about how many.

I’ve gone through and added/removed all of the buddy press components, and as soon as I have more than about 5 of them, I get 500 errors no matter what page it tries to load.

The fix for me was to make a file named php.ini, and within that file put:

memory=20MB

…and upload it to the wp-admin folder.

Basically 1and1’s PHP limit is probably set to like 8mb or 16mb, and BuddyPress is just too big for those britches. Of course, you can increase your memory size to whatever makes it work for you, but 20MB should be plenty.

I also put:

AddType x-mapp-php5 .php

AddHandler x-mapp-php5 .php

…in my .htaccess file at the root directory to make sure 1and1 knew to give it php5 and not the 4 that it tries to give by default. Silly 1and1…