@valerostudio said:

I have had this same issue in the past. Make sure there are no characters in your file name at all, even the folders. We had an "&" in our project name that VR did not like that at all.

Now I also render all finals into a folder on my desktop to shorten any issues with folder structure as well.

Thank you for your reply. Good to get this tips about bugs discovered by experience!

About the Vray Frame Buffer I still think it is a bit rigid and something as useful as recovering a past file rendered in it should be possible. It is quite easy to loose work with how it works...

I am curious, is there something in the 3ds max Frame Buffer that Vray could still learn from?