Cannot find games following a hard drive change

@SierraLeone4  Open a File Explorer window, click This PC in the left panel, and enter TS3.exe in the search box in the upper right corner.  This should turn up a Bin folder with both TS3.exe and TS3W.exe, among other files.  (You won't see the .exe if you have File Explorer not to show file extensions.)  Please click on the TS3.exe entry, select Open File Location, copy the file path (above the list of files and folders), and paste it here.

Please also let me know whether you most recently played with discs or through Origin.

@puzzlezaddictUsually, I click on a Sims 3 icon on the desktop, not through Origin, which makes me think that I play with discs. However, I'm fairly sure that a disc is not inserted each time (so can play without a disc?). I found the TS3.exe files but there are 12 of them, I'm not sure which one to click on. Oh gosh, I'm so unacquainted with IT language that I feel totally lost, lol.

@SierraLeone4  If you have to sign into Origin to play, that makes it easy.  Open your Origin game library, click on the Sims 3 icon, and press Play; if you don't see a Play button, click on the gear (Settings) and Locate Game, then point Origin to where your game is installed, basically to the Sims 3 folder that the TS3.exe copies are nestled inside.

If you don't need Origin to be open, the answer might be a bit different depending on the structure of your install.  Most people who've bought packs on the Sims 3 site end up playing through Origin, so I'm not actually entirely sure how things work for the few who've managed to avoid it.  At any rate, what is clear is that the shortcut on your desktop is damaged or points to an invalid location, so you'll need to trash it and create a new one to the proper .exe.

Among the dozen or so copies of TS3.exe, look for a TS3W.exe (with the W) that's inside a folder labeled EP08 (Seasons is your newest pack and the eighth expansion released.)  Try just double-clicking on TS3W.exe and see what happens.  If that doesn't work, try the other executables in the EP08 folder; this is a good time to allow file extensions to show in File Explorer.  I know older disc copies used something like TS3EP08.exe, I can't remember the exact name, so you may need to experiment a bit before you figure out which one works.

Once you know which .exe launches the game, you can right-click on it and select Send to > Desktop to create a new shortcut.

@SierraLeone4  Try running the Super Patch:

https://forums.thesims.com/en_US/discussion/175477/official-ea-download-link-for-the-sims-3-cumulative-manual-update

You may need to try to run it on a few different files before you find the one that the Super Patch is designed to work on; I've actually only ever run the Mac version of the Super Patch, so I'm not totally sure how it works in Windows.  But it'll be somewhere inside those program files.

If that doesn't work though, it's possible that the relevant registry entries for Sims 3 are now missing, and that without any way to rebuild those, you won't be able to run the game.  In that case, you'd need to do a clean uninstall and then reinstall through Origin.  I'd still run a program like Piriform's CCleaner to clean up any stray files, in case there are any floating around.

@SierraLeone4  You could search your computer manually, but the easier path is to use a tool like Piriform's CCleaner (mentioned before) or Revo Uninstaller to remove all Sims 3-related files.  This can be done before or after you've uninstalled a program manually, so it's not a big deal if you can't uninstall through the Control Panel.

Personally, I'd probably use Revo to do the uninstalling, then run a pass with CCleaner just in case Revo missed anything.  Both have a free version that tends to work fine.

If you want to preserve any saves or other content you created, it'll all be in Documents\Electronic Arts\The Sims 3.  It's a good idea to at least rename this folder, so it's not picked up by either scan, and even better to back it up on an external drive or USB or upload a copy to cloud storage.  But if you don't mind starting from scratch, don't worry about it.

@SierraLeone4  I haven't used Revo Uninstaller in a while, probably over a year, but I'm surprised it isn't picking up any Sims entries.  Can you navigate to the location where you found various copies of TS3.exe?  You can also search for the names of packs or their designations, e.g. Ambitions or EP02, and see what you get.

If this doesn't help, try CCleaner.  The point is to find something that will sweep your hard drive for any Sims 3-related files; it doesn't really matter which tool you use.

If you can't get Revo to work and CCleaner isn't being helpful, I'll download them again and mess with them a bit.

Ok, so what I just did now was finding each Sims 3-related files and deleted them one by one. When I right-clicked on these files, there was no 'uninstall' option, that's why I clicked 'delete'. Then I emptied the trash bin and ran CCleaner afterwards. Note that the search bar of CCleaner, just as Revo, couldn't pick anything while I typed 'Sims' or 'TS3'. Then I uninstalled Revo and CCleaner and downloaded them again -same thing again.

In absence of Sims related-files showing up, is it reasonable to think that Sims 3 is wiped off for good? Is it safe giving a try to reinstall the game now?