Error Code 16, corrupted saves

OvR8d1  I have a few suggestions in this master thread, which I wrote for Sims 4, but the OneDrive-related settings are the same:

[CURRENT ISSUE] Sims 4 saves/user content disappearing (PC) | EA Forums - 11838402

I've heard from some users that some options aren't the same on their devices, so if you don't see one option, just move on to the next one.

There are two other approaches I didn't list in that thread as well.  One is to create a separate admin Windows account for playing Sims 3.  Make the account local (no link to your Microsoft account or any email address), and you won't have any link to OneDrive.  So you won't have to change any settings about your main account, just switch accounts when you want to play.

The other approach is one I can't promise will work because I don't have this issue myself.  It could work in theory, the principle is fine, but I would need someone affected to test.  That is to create a symbolic link to move your Sims 3 user folder, or the Electronic Arts folder, elsewhere.  This guide is also for Sims 4, but the process is exactly the same other than the folder name:

https://crinrict.com/blog/2020/02/moving-windows-documents-folder-to-external-drive-via-symbolic-link.html

You'd want to tell OneDrive to always keep the symlink on the device, as in the first link.  You could direct the folder anywhere on any drive that isn't within a OneDrive folder, and the content itself should be intact.  What I don't know is whether when Sims 3 can't write to the OneDrive folder, it can still jump through a symlink to write elsewhere.