Most of us working with zModeler have likely experienced or at least heard of the infamous "RC20 - Invalid Resource Detected" crash that can occur with cars that we've built. I've recently experienced 2 particularly nasty and seemingly un-fixable RC20 crashes with 2 separate cars this week. 

 

I've spent the last 3 days researching everything I can get my hands on regarding this crash but the general answer seems to be, "no one really knows what exactly causes it."  We've got quite a few experienced people here, and even more inexperienced people who are eager to learn, so I thought I would reach out to the rest of you and see if anyone has any suggestions on how to overcome the RC20 crash, and how to avoid it in the future.

 

First, a little humor before we go on...

 

 

 

The first time I encountered the RC20 was with a Dodge Charger I was working on a few months ago. When it happened, I was able to roll back to a previous save and re-build the car from there without any further issue.

 

Last week I was putting finishing touches on a Ford Interceptor Utility I've been working on when the RC20 happened. I rolled back to a previous save, a previously WORKING save that I had tested in game just minutes earlier, and to my surprise it was now also experiencing the RC20. I ended up having to roll back 5 saves to find one that was working. I spent a few hours rebuilding the car from that point, testing in game along the way, only to encounter the RC20 again.

 

At that point I gave up out of frustration and decided to try again later and I switched gears to a Tahoe. I spent all day putting the same equipment into a Tahoe only to once again encounter the RC20 crash during final testing. Same issue as before, I rolled back to a previous save and they were now also having the RC20, when they were fully functional before.

 

Logic might suggest that the equipment I'm putting into the cars might be the problem, but I've used the exact same equipment on 3 other cars so far without any issues so I can't believe that would be the problem.

 

What about you guys? What have you done to mitigate the RC20?

I rename any materials with the same name in the materials editor and that seems to help a lot. That and attaching all the extras. So instead of having a bunch of misc_whatever, I usually attach all the misc equipment for the vehicle.

I've only come across the RC20 error when a I leave a texture loaded in the "default material". For some reason if I leave a texture loaded in there it textures some of the COL files and it causes a RC20 error.

I rename any materials with the same name in the materials editor and that seems to help a lot. That and attaching all the extras. So instead of having a bunch of misc_whatever, I usually attach all the misc equipment for the vehicle.

 

I'll have to sort through that. I have noticed that I have a lot of duplicate materials with the cars I've built, sometimes the same material will appear 2 or 3 times in the materials list. I'll start renaming them and see if that helps, thanks for the tip.

 

I've only come across the RC20 error when a I leave a texture loaded in the "default material". For some reason if I leave a texture loaded in there it textures some of the COL files and it causes a RC20 error.

 

I'll check that too. I've not intentionally messed with the Default Material so it might have gotten changed without me knowing. Thanks!

The RC20's I have run into have mostly been with the collisions. I would be interested in finding out where the issue lies.

I have been having RC90 nightmares very similar to johnclark1102. My current build RC90'd a few times, worked once then went back to RC90-ing. I was going to start my own topic until I happened on this one. I double checked no materials in "default materials" and removed collision objects other than the base CVPI (bxbugs). With this latest export, it now works! 

 

Interestingly enough, when I turned the collision objects on for my lightbar (PFC's liberty) hadn't moved with my lightbar during assembly/positioning. This meant that the lightbar collision object was within the CVPI collision object. I didn't need to move the rambar but decided to delete its collision object anyway. I might do a quick test at some point with another car testing collision objects on/off. 

 

RC90 seems to do with collisions as TheGTAMitch suggests....

That's good to know.

 

I was able to get my car working by starting over and ensuring there were no duplicate materials. Turns out there were quite a few, because I didn't know any better when I started building the car several months ago. I ended up going back and rebuilding the car with some of the new techniques and experience I have and it's working now.

 

It could also have been an issue with me accidentally moving a dummy or something too though, but in any case it's fixed.

 

I do think it might have something to do with the collisions, specifically the windows on my car. I've had a lot of trouble with them, they don't currently break, and through investigating that it turns out there are actually two windows on top of each other and they are not 3 dimensional objects in zModeler so it's really hard for me to tell which one I have selected so I can delete the extra window. It's an ongoing project...

I seem to encounter RC20's with some models more than others, such as Dhruv's 2012 Charger

I seem to get RC20's when I try to put to much badassery in a model. Makes it too high poly. Or too many textures.

RC20's are most often caused by the default_material shader conflict that occurs on export. Reimport unlocked, find the issue, fix, fix rc20!

 

There are other causes for this, but it seems that default material is the most common.