Re: Service initialization failed 0x039e8474
@leahmay74 Sims 3 is programmed to look for and store user data in the Documents directory regardless of where the game is installed. In a way, it's makes things a lot simpler—you can make changes to your saves, mods, and other user content without messing with the game's program files, where one mistake could mean reinstalling everything.
If you want to move the entire Documents directory to your larger drive, that's simple to do and supported by Windows. However, you should only do this if the second drive is internal; if it's external and is ever disconnected, Windows may react badly.
https://www.tenforums.com/tutorials/74952-move-location-documents-folder-windows-10-a.html
You didn't mention whether your secondary drive is internal or external; if it's external, using a junction is your only good option. As for the drive letter issue I mentioned, I don't actually know that that happened, I'm just suggesting it as a possible issue for an external drive. The way to prevent it is to always plug in your devices in the same order, since Windows assigns drive letters in the order it reads the devices.
Windows itself should always be on your fastest drive regardless of its size. Moving it to a larger, slower drive would cause a significant drop in performance, enough so that you'd notice even in some basic tasks. Everything else can be moved to another drive if necessary, for example you can move Photos or another user directory to a secondary drive in the same manner as above.