Ive had the same setup for over a year with n o issues. I went to look back at the playback of a camera the other day and it wont play. If i highlight it in the calendar window it will start to play the preview. Then click for it to play what ive selected, the screen switches back to the playback screen. The first box blinks a red ring around it but nothing ever plays. Ive tried a firmware upgrade, factory reset, reformatting the drives with no change. Im using IE11.