Looks like you are using ‘almopst pretty’ permalinks i.e. has /index.php/ at the beginning. BuddyPress insists on ‘pretty permalinks’ you need to get rid of the index.php. If you are using an Apache server this is easy – just take it out. If you are on Zeus for example then you will need a rewrite script.
can u explain.i dont get,just example,
how can i rewrite.and were plse helpe me
Take a look here https://codex.wordpress.org/Using_Permalinks where the difference between the types of permalink are explained. You have the /index.php/ in your permalink settings.This is probably because your hosting provider needs them for your normal WordPress to work, I notice you have reverted to the default which wont work for Buddypress anyway.
Ask your hosting provider for a rewrite.script file so that you can have ‘pretty permalinks’
