When I first click Origin open, it says Updating Origin and goes through a little update bar all the way to the end. Then when it should be finished another window pops up instead and says UPDATE ERROR: Your update could not be completed. Please download and install the latest version of Origin from.." with a link to the website. Then I go and reinstall, and it opens and I click "play" on my TS3 game. The launcher comes up fine but after I hit play I get a black screen that does nothing else until I restart my computer all together. I can't figure this out!

I'd also like to add that I just completely removed the Sims 3 folder from my Electronic Arts folder. I launched the game (it worked) to regenerate all of the files and folders. Then I closed it, and placed all of my sims3pack files into the new Downloads folder, and all of my game saves into the Saves folder. I cannot get the game to open!

I recently converted all of my sims3pack to package files and scanned with Delphys Dashboard and none were corrupt. I've since gone back to using the sims3pack, but wanted to mention that my CC is not bad (or shouldn't be, since nothing was flagged in that program). I have about 4,500 CC. I've been playing with no problems until recently. I started crashing, and figured out I had a bad save file. The crashing has almost completely stopped, only now I can't even get into my game!

Can't help with Origin but when it comes to the Dasboard, it is not by any means 100% accurate. You can bad cc without it noticing it(them) at all. It's a very good program to have but do not trust it completely.

Your installed sims3pack content would not be in Downloads, nothing needs to stay in there after installation. The content would be in bundles in the DCCache folder. If a saved game relies upon a world that is not from the base game or an EP to be installed, then it won't start until that world is installed again.

On the Origin issues, it could be something as simple as clearing the Origin cache. But I would suggest bringing that to the team at EA's AHQ forum so they can help you troubleshoot it properly.
https://answers.ea.com/t5/The-Sims-3/bd-p/the-sims-3

I had to put them back because I needed to reinstall them And I'm only playing with worlds that come with the base game or EPs

I did fix the origin problem from the solution given here https://modthesims.info/showthread.php?t=653070

This just put the game into a small square and unfortunately the game was still unable to load

I had the "black screen" issue at one point and the advice I got from this thread, third post fixed it for me. I suspect it came from downloading sims from the exchange, and now I never, ever download sims.
https://modthesims.info/t/553216

THANK YOUUUUU this helped!!

I do however have a new issue haha always. When I finally got back in, all of my CC was missing. I uninstalled and reinstalled all of my CC and a lot of it is showing up now, but not all of it.

Make sure you have all your expansions "ticked" in the one tab on the launcher.

The only one I leave unchecked is Into the Future because I never use anything from it and it just seems unnecessary to have it ticked. So I have it installed and if I ever want to use it it's there, but I haven't ever used it since I started using my TS3 game on my new computer about a year ago lol.