Can't install Elgg 1.5!


   I have recently downloaded Elgg 1.5 Full Package and tried to install it on a Xtreemhost Server, but it keeps on failing. I have all the required System Configurations, the problem is that whenever I get into the third step, it keeps on saying that the data folder is not writable, while the data folder is stored outside the Elgg Script and is fully CHMOD to 777 Permissions.

   Please help me, in installing Elgg, because I need it badly, while it keeps on showing up that error!