Applicable to the 32-bit version of Sims 3
Open Origin and go to Preferences (click on Origin, top left next to the Apple logo). Make sure you are under Installs & Saves.
Enable Keep legacy game installers and change the location of the saved installers (disk images) to somewhere easier to find*. I suggest creating a new folder in your Documents folder and calling it “Sims 3 game installers”, or something similar.
If you haven’t ticked the box but downloaded the game you can do the following. This has to be done BEFORE you install the digital download as the disk image and mounted installer disappear as soon as you’ve downloaded the game:
- download the game from Origin
- when the installer window pops up ignore it, open a Finder window and navigate to the following:
Macintosh HD > Library > Application Support > Origin > DownloadCache
- in that folder will be the disk image for your download. The file name will start sims3_ep9 (with the 9 indicating the EP, this number will change depending on the EP you have downloaded). Select, but don’t double click, the file then click on File > Duplicate.
- wait for the file to be duplicated then move it to another location on your Mac.
- you can now carry on with the install, safe in the knowledge that you have copied the disk image for future use.
- when you want to reinstall the EP simply double click the moved disk image and it will mount the installer on your desktop, ready to install.
By saving your Origin disk images you won’t have to waste time re-downloading the digital EPs and SPs in the event of a reinstall.
If you are installing on a new Mac you don’t even need Origin installed for this to work. Just copy the disk images onto an external drive, plug it into your new Mac and start installing.
*Thanks to godzillasims for pointing out this option to me 😳
Bluebellflora 
Thank you so very much for this. I was going spare trying to find any information on what seemed to me like an obvious feature – like, why doesn’t Origin keep the game installers by default, or ask you before installation whether you want to keep them or delete them? It’s annoying that the way to do something so necessary is hidden away like this.
Thanks to you, though, I know its hiding place, and don’t have to get stuck downloading all over again any more. If I could, I’d buy you a Terry’s Chocolate Orange.
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yummy – thank you! 😉
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what if i didn’t do this and now my sims 3 supernatural won’t play
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Uninstall Supernatural, redownload and reinstall.
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i tried that but i cant find where to uninstall it at. i tried looking on origin and there is no option to uninstall it
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Applications > The Sims 3
There is an uninstaller in there. If there isn’t then follow my instructions on the uninstall page to uninstall it manually
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okay so the weird thing is when i go to sims three uninstaller it doesnt show supernatural and yet origin says it is installed
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So somewhere in the installation it’s screwed up. Origin thinks it is installed but it isn’t. You could try deleting all files relating to Supernatural (refer to the clean uninstall/reinstall instructions) uninstalling Origin (and any residual preference files) and then reinstalling Origin and Supernatural.
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okay i will try that and let you know how it goes. thank you so much for all of your help ive been working on this for two days now
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Yeah, TS3 on Macs is real labour of love! Good luck 🙂
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i uninstalled everything and so far i think it worked! i am redownloading the sims 3 base game and going from there. i will keep posting on my progress.
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🙂
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Hi BluebellFlora,
Your guides and How-tos are a big help. I’ve been a long time Simmer (since Sims1) but have recently switched from Win to Mac.
I can’t seem to find a straight answer for this question : Can I run Origin, the Sims 4 games and its future EPs from an external drive? My Macbook Pro only has 120G or so storage, with the Sims4 and other apps (not to mention any EPs I will be sure to install in the future) I would need more. I can place apps on an external drive and run them through there.
Can I do the same with Origin and the Sims 4 game including EP/GP?
Appreciate your help. Hope to hear from you soon.
All the best!
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You could try. A lot of Simmers with MBAs did this for TS3.
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Do you need to have Windows programming as well on your Mac? It won’t let me download Origin because I don’t have Windows…
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Download or install? You have to download and install the Mac version, not the Windows version! https://www.origin.com/gbr/en-us/store/download
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does this still work?
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I tried doing it, but I can’t find the disk image
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Which game? Yes for Sims 3, maybe not for Sims 4.
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