406 Not Acceptable page

Please use descriptive titles on posts.

Your server is configured to prevent those capabilities from working. Likely an Apache security module.

so Actually what you're telling me that there is a plugins that not safe to the server ( i call to the host provider and he tell me that is Not recommended to cancel Mod_Security and elgg have a lot of Known security problems

You can explain it better?
Thanks, Kobi  

[Admin: removed for being off-topic]

406? This is why we can't have nice things....

Elgg does not have any known security issues (which is different from saying that it doesn't have any security issues which are not known at the moment, of course).

Here is a link about this: http://trac.elgg.org/ticket/1753

The short answer is the mod security doesn't like "http" included in a request parameter. 

Why don't you contact your host's technical support and show them your URL similar to this

javascript:location.href='http://community.elgg.org/mod/bookmarks /add.php?address='+encodeURIComponent(location.href)+'& title='+encodeURIComponent(document.title)

OR

javascript:location.href='http://community.elgg.org/mod/reportedcontent/add.php?address='+encodeURIComponent(location.href)+'&title='+encodeURIComponent(document.title)

and ask them to "WhiteList" it in mod_security configs ? It is the format of the URLs that mod_security is detecting as potential threat. Others have had this same issue in the past and the only way out is via your Tech Supp. That should get rid of the "406" ;-)

[Admin: this post has been removed for being off-topic. A new thread should be created for a different topic]