Decided to run Windows Disk Cleanup and selected "Cleanup System Files" The scan found 3.99T (that's "T") of files under Windows Update Cleanup. How can that be? I only have 1.8T of total hard drive space (2 hard drives)! Didn't dare delete any of those files in that category. Thanks!!
Yes, it is completely safe to delete these.
An explanation here...
Cumulative Update KB3197954 Windows 10 PC and Mobile build 14393.351It's not exactly a bug, there really are 3.99TB of ntfs directory entries to clean up (or more, 3.99TB is probably just the highest number it can count up to). The fact that 99.9% of them are hard links that don't actually occupy additional physical disk space makes little difference...
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