2.5.0.5 is the most recent version of iVMS 4200. I would check to make sure you have the right firmware in the camera too. Are you recording to a NAS or something, or are you just using iVMS 4200 to live view the cameras? If that's the case, try deleting the whole server/device list, and repopulate them back into a single group for viewing, 4200 can be finicky at times when replacing cameras using the same IP.