Attention .max is possibly corrupt

[tricky]

What is this error? It shows its face from time to time and when you try to re-save as it suggests, it tends either not to work or corrupt the max file.

I had just rendered an image using DR but as you can see in the background of this screen grab, there were lots of black buckets. I have a couple of XREF scenes in this file, so I cloned the vraycamera and tried rendering a small region to see if that solved the problem. Upon clicking render, this error message pops up.

What is it?

How do I stop it?

Its happened for several years now, though only once in a blue moon.

[Rens]

Are you using a bercon gradient in a composite map?

[tricky]

Just to follow up, if you click 'No' to the offer to re-save (because choosing 'yes' doesn't work anyway), vray will continue to try and build the lightcache but carry on forever. The only way to stop it is to cancel the .max process from task manager and re-start max. The problem then is that the scene is corrupted.

(fortunately we have MANY backup scenes!)

[AJ Jefferies]

I get this error whenever I hit save on a large file then hit render before it has finished saving. Not sure if this is what's happening here but I catch myself at least once a month with it!

[tricky]

Are you using a bercon gradient in a composite map?

Nope. No bercon grads as far as I know. We use bercon tile though (for the floor) and perhaps bercon noise in the odd material here and there.

[tricky]

I get this error whenever I hit save on a large file then hit render before it has finished saving. Not sure if this is what's happening here but I catch myself at least once a month with it!

For us it happens just as you click render.

[cheerioboy]

do you have auto-backup enabled?
I used to get that issue all the time until I disabled auto-backup

Not sure if it's poor timing of the auto-backup in conjunction with the saving when you run DR...

[tricky]

Couldn't live without auto-backup so wouldn't like to try it.

[Neilg]

For us it happens just as you click render.

That's because it starts autosaving just before you click render. Max goes 'right, i'm gonna autosave now', the rendering starts, then max tries to start writing to disk. There's a slight delay which gives just enough time to press render - It's the same issue as the manual save one.
I've started a couple of threads on this topic before. if you've been rendering for 15 minutes, cancel, change a setting & press render it seems like the timing is perfect to have this happen.

I've not seen it for nearly 6 months just by giving max a little breathing room between saves and renders. I also try to avoid cancelling and starting a new render straight away - give it a minute or so.
e: I also use WAY more xrefs to keep my main file size down. if you're spending 5 minutes saving each time you'll see it a lot more. So now things like furniture get placed in a scene with the walls set to non renderable and xref'd in with lights disabled (so I can still do test renders in that scene for materials etc).
I also just prefer working that way now, my main render files are tiny and i've got 4/5 xrefs which can each be worked on separately.

[cheerioboy]

I've just learned to save often - which I was pretty much doing before disabling auto-backup anyways

But it would be great if it wasn't an issue we had to deal with

[tricky]

I also try to avoid cancelling and starting a new render straight away - give it a minute or so.

Yep - we've been doing this for a while too. DR hates having renders cancelled and then started again.

[mcnamex]

That's because it starts autosaving just before you click render. Max goes 'right, i'm gonna autosave now', the rendering starts, then max tries to start writing to disk. There's a slight delay which gives just enough time to press render - It's the same issue as the manual save one.
I've started a couple of threads on this topic before. if you've been rendering for 15 minutes, cancel, change a setting & press render it seems like the timing is perfect to have this happen.

I've not seen it for nearly 6 months just by giving max a little breathing room between saves and renders. I also try to avoid cancelling and starting a new render straight away - give it a minute or so.
e: I also use WAY more xrefs to keep my main file size down. if you're spending 5 minutes saving each time you'll see it a lot more. So now things like furniture get placed in a scene with the walls set to non renderable and xref'd in with lights disabled (so I can still do test renders in that scene for materials etc).
I also just prefer working that way now, my main render files are tiny and i've got 4/5 xrefs which can each be worked on separately.

i concurred with cubic on this one. sad but true

[alexyork]

One thing - how much free space do you have on C or whatever drive you're using as your scratch/temp disk? If you are very low on space (maybe you're using a small SSD) sometimes max/vray can't write temp files when trying to render or save scenes/calculations/renders and will crash or error out. You might be surprised how much disk space is used up when you open a large scene, mess around with it, save it, render it and then try to do this 20-30 times over a day without closing max. Suddenly your OS drive can be reduced to a tiny amount of free space and things start going bad.

Just worth checking.

[Svetlozar Draganov]

Couldn't live without auto-backup so wouldn't like to try it.

It would be a good idea to turn it off for a while and if the issue goes away then we will know for sure what cause it.