Hi, I am having exactly the same problem. It started a few days ago, prior to that never had an issue, I’m using Pro 9.5 on Win 10 64bit and three times this week my cpr files have just vanished. I even did a copy of the project one day by doing “save as” with a different name so I would have to identical versions and both vanished. Luckily all the back ups are still there and I have been able to load one up without losing too much work but it is worrying. I am now making a copy of the cpr file and saving it to another drive for added safety but it is a pain. I hope someone is able to answer this question for you ( and therefore me too! )