BuddyPress.org

@hami007 best thing to do would be scrap the free hosting for a start as when errors like this occur you may find you are limited in what you can do to troubleshoot issues, like hugo said it sounds like you need to check all your plugins 1 by 1 as a starting point then i would at least look into some cheap basic hosting rather than free, there are some great deals on shared hosting around that are really really cheap but to be honest running wordpress and buddypress on shared hosting further down the line will probably end up failing you due to restrictions and overuse of the server etc etc, at least look into getting an half decent vps server to start off with and learn the basics of server maintenance before moving on to the likes of dedicated servers etc though, i jumped straight from shared to dedicated and found myself lost and at mercy to linux as a novice user, so i decided to take 8 months time out and learn everything about linux server hardening and security i could alongside the correct way to set everything up for running multiple wordpress websites etc etc, it all sounds daunting at first but if you stick with it or at least move away from free hosting it will be worth it with time and effort. just a little advice for you before looking for a real hosting solution as i kinda jumped into the deep end, as i have read so many stories of people who went and got a good deal on a dedicated server etc that didnt have a clue how to use it but found themselves in a 12 month contract, luckily i wanted to spend the time learning myself so it paid off for me.