Compact Material Editor Problem

[Argyll46]

I opened the grass tutorial and it worked fine, however, when I opened the material editor and tried to create a new material I get a Parameter  error as shown in the attachment. If I click on the material button in order to change it from Standard to something else I get the same error and eventually after 4 or 5 attempts, 3ds max (2012) crashes. If you can't create materials in the material editor..... that's a real  problem.

[iToo]

I cannot reproduce the problem here (Max 2012 64 bit, Forest Lite 3.6.0), so there must be some difference with your configuration.

What version of the tutorial have you downloaded, Mental Ray or VRay ?
Do you have VRay installed ?
Do you get other errors or warning messages while loading or rendering ?

[Argyll46]

I'm using mental ray and can produce this error almost at will. I had it happen four times in a row yesterday and once today. I have the latest service pack for 3ds max 2012 installed so don't know if that's causing a problem. Also, I'm running a 32 bit app on 64 bit W7, so it may be a bit flaky. I really like what the software does and will probably purchase the pro version as I'm gradually coming to terms with it, but this type of crash is a bit of a worry.

[iToo]

So, did you get this error also working with other scenes, not only the grass tutorial ?
 
It seems there is some file corrupted in Max (because the "File Open Error" title of the error dialog), probably something related with the materials.
 
If you are worried about whether Forest Lite is triggering this error, i would suggest uninstall the plugin temporary and see if the problem remains. Sincerely, seeing the symptoms, i think this error is not caused directly by Forest. Similar issues have not been reported by other users either.

[Argyll46]

The error was with every scene. I've reinstalled 3ds max and Forest Lite and everything now seems to be working fine so I guess and it's only a guess, that one of the 3ds max files was corrupt - I got the error after uninstalling Forest Lite and running 3ds max on its own.