@Hum4n_n4ture It looks like the caution is coming from OneDrive, probably that some files aren't being synced properly. One common reason for this is OneDrive being full, but it can also happen because of connection or system issues.
The inability to sync files isn't an problem all by itself—as long as the content is present on your hard drive, Sims 4 should load it. But you'll probably want to stop OneDrive from automatically syncing regardless, since this can cause problems down the road. Here's how to stop the syncing:
Keep in mind that this can remove some files from your hard drive and leave them only in OneDrive, so you may need to manually redownload those files afterwards. Just check which files are still stored locally and replace the rest as needed.
You could of course clean out OneDrive to free up space, but that just pushes the issue down the road. What you definitely don't have to do is buy more storage from Microsoft; that's a waste for most people.
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