I have had the absolute worst luck with these cameras.  I have 7 of them, and 3 have failed and been replaced by DLink.  And now I have two more that have failed.  The whole system is only 6 months old.  
The problem is always the same.  The cameras freezes up and when you log into the admin page its showing a freeze frame from days ago.  You reboot the camera and you get one frame and it freezes again.