Don’t ever remove /dev/null. Don’t remove /dev/null on your server. This leads to very strange effects.
You can’t get email’s. Your cronjobs don’t run in the espected manner. Your system is not OK if you ewer delete /dev/null. If you do that ? Or if you have do that right now then you have a BIG problem.
No attorney, no law, nobody can help you 
. But there is a trick and the trick is ….
To make the node again.
But what is /dev/null :
Here are few words from wikipedia :
In Unix-like operating systems, /dev/null or the null device is a special file that discards all data written to it, and provides no data to any process that reads from it (it returns EOF). In Unix programmer jargon, it may also be called the bit bucket or black hole.
The null device is typically used for disposing of unwanted output streams of a process, or as a convenient empty file for input streams. This is usually done by redirection.
This entity is a common inspiration for technical jargon expressions and metaphors by Unix programmers, e.g. “please send complaints to /dev/null” or “my mail got archived in /dev/null“, being jocular ways of saying, respectively: “don’t bother to send any complaints” and “my mail got deleted”.
read the rest on http://en.wikipedia.org/wiki//dev/null/
And if you have deleted it, make this NODE again.
The command is : $Â mknod -m 666 /dev/null c 1 3Â Â