Here's what I find @ZeeGee -
http://steamcommunity.com/sharedfiles/filedetails/?id=255005284
See if this helps you. Remember that there is the option to hide folders, so you might have these folders normally hidden?!
In case of hidden folders:
1
Open File Explorer from the taskbar.
2
Select View > Options > Change folder and search options.
3
Select the View tab and, in Advanced settings, select Show hidden files, folders, and drives and OK.
And, your goal is to simple move out the registry keys, not delete them. That should let you just copy the keys back in again as you wish.
The key part is:
press Start, type 'regedit', navigate to 'HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Sims(Steam)'
Here you'll see the expansion packs and stuff packs and additional folders!
Also key is the fact that a suggestion is made to backup your registry before you begin in case of any error!!!