When I go into CAST I get the loading screen 'materializing materials' and it just loads and loads and loads. I figured this must be a corrupted pattern file, but here lies the problem; I downloaded some new objects and used the sims 3 multi installer to convert them to packages. Now I have no idea how to pick out which are the pattern files. I would rather not delete a couple hours worth of cc shopping. Is there anyway I can fix the materializing materials without deleting the patterns, or is there a way to find out which package file is which?

The "Materializing Materials" error is caused by patterns, indeed - specifically, by a pesky extra space somewhere in the coding. This is a risk with converting patterns from .sims3pack to .package, and why many creators advise people not to do it. The good news is that it's very easy to fix and you don't need to go through all the patterns, and you can keep your patterns in .package format and avoid the cluttered Launcher. You can find more information on why it happens here, and here are 3 ways to fix it:

1) manually, using S3PE: here;

2) mass fixing, using Granthes's program: link | mirror (reuploaded because the link in the thread is dead). Extract the archive, then drag and drop your patterns on the MMFixer.exe file. A few extra files will be created, you can delete those;

3) manually, using Postal:
1. open your pattern;
2. navigate to the XML entry;
3. find the "reskey" part (should be near the end of the first line; outlined in red in this screenshot);
4. make sure there are no spaces in the field that I marked with red. The screenshot above is how a proper pattern should look like;
5. click "Commit" and save your pattern.

UPDATE: I don't know whether patterns made with the Create a Pattern tool, then converted to packages, are a cause for this error, but Oh My Sims! wrote a very helpful guide on how to solve it here: https://ohmysims.tumblr.com/post/122673018070
This is also helpful if you run into the "one pattern overriding others in the catalog" issue.

Moving to Help. Please use the Help forum for Help questions, not Discussion.

Thank you SO MUCH!!! You must be some kind of god or something. I've been looking for this thing for days!

I merged some packs and patterns and then deleted them but my game is still doing the Materializing Materials glitch and I don't know how to fix it, can someone help me get my game working again?

Did you remember to clear your caches after deleting the merged packages?

which caches folders do I delete?

http://simswiki.info/wiki.php?title...ete_Cache_Files tells you where to look for the cache files and which ones to delete.

Or you can do what I do and use the Dashboard http://www.modthesims.info/download.php?t=387006 and find the function it has to clear caches. This makes sure that the right files do get deleted and the wrong ones don't. (Although it's possible to clear the World cache, which is something that you should never do on a MAC install.)

I have encountered this error. Here is what I have done, I uninstalled all the sims3pack files of patterns. I took out the mods folder, redid the frame work, added the cc back in. Deleted my cache. My materials are STILL materializing.. I can see nowhere that I have a pattern file in the launcher. I read that patterns, if installed through the launcher do not produce this error, but it did for me. I have no idea why I still have this error, and I have been trying to fix it for two days. I have next to no custom content installed and only about 3 patterns until I downloaded more. CC magic did not really do anything just showed me what I had in it, and I went through and deleted all the patterns in there too. I am at a loss, I have like 1 and a half gigs of cc in sims 2 never a problem, barely anything in three, and cannot play the game to save my life! Guess I will not worry about changing appearance. What a frustrating error! I REFUSE to sit and reinstall them all too..

Have you rwad the thread you're replying to? You would be surpriced how many people don't do that. There is a post further up about suggestions in 2015. Did you try them?

I removed all patterns frst, I downloaded the Granthes's program and tried to drag/drop the patterns onto it like it said but it kept telling me that there was a error reading the file. I have patterns downloaded (not installed), but thought if they were all out of the game then I wouldn't get the error. I am going to go through the cc content again today, there has to be something there I missed. I want to fix the error before I try putting anymore patterns in it.

Are the patterns old? If you have very old patterns I would not use them. There is also programs like Custard and Multipackinstaller from Delphy that can tell you if some of them are faulty. If you still can't make it work, I would make them all into package files and take the 50/50 metods, if it's that important to you. That means after converting them, take 50 out of the mods folder, start the game, if it doesn't work take 50 more out, or if it now works take the working files out and try the last 50 in instead. Continue like this until you know what file is faulty. It's going to take a lot of time, and you have to think about how important it is for you.

I know people say patterns shouldn't be converted, but taking out a sims3pack file that doesn't work is a pain in the butt and very often it doesn't work. For that reason I convert everyting, but if I'm going to play the house, I won't convert kitchens, that's all.

Yes, this is what I have been doing the last few days! Which is a pain. When all was said and done I removed about 6 files that were bad. The strange part is that it was package files that were the culprit, which is rather strange since I have not installed package files for a good six months or so and it worked fine. All of the patterns I installed were through the launcher. I am finally done, and I can access it again at least. Man, I love sims 3 but it sure can be finicky! Thanks for your help, this was the first time I had encountered this error and was a little lost!

Some say it depends on how they are made. EA has this pattern tool and like most things EA make, it's faulty. Others use community made tools which works better. There is one pattern creator on TSR I never use because her patterns always bugs up when converted. Her patters are very old though, but sadly looks very nice on the wall.

Thank you! very helpful!