Checking over my Insider Preview Fast Ring system/boot drive (C:\) this morning, I found something new and interesting. It’s a hidden, read-only folder named $WinREAgent. Folders that start with a dollar sign are usually hidden, created during installation for temporary use. I’ve seen plenty of such things come and go over the years, but this is the first time I can see this one. Its creation date is October 8, 2019, which coincides with Build 18999. I suspect that Windows 10 now uses this folder during installation to set up the recovery partition — as Kari documented in his November 13 story “Thank you, Microsoft …” — at the tail end of the system/boot drive. Here’s what this looks like on one of my Fast Ring PCs (Lenovo X380 Yoga):
It’s a new one on me, and seems likely to be a leftover from the Windows 10 Installer: $WinREAgent.
[Click image for full-sized view.]
Not Much to See in $WinREAgent, Either
Further investigation shows the size of the folder to be 0 bytes. There’s a single sub-folder, also empty, suggestively named Scratch. Searching MS DOCs and the Microsoft site, I find no mention of it anywhere. Just for grins, I ran the Disk Cleanup alternative program, Managed Disk Cleanup for Windows. I checked all of its available boxes, except for Downloads and Thumbnails (both of which I prefer to keep around). That folder did not get cleaned up using the tool.
But although I had to grant admin permissions to remove them, delete inside File Explorer worked for all three “dollar-sign” folders shown above. I guess that means there’s another item to add to the list of post-install cleanups for those who, like myself, prefer to clear away all the unnecessary (or empty) leftovers after the Windows Installer does its thing on a feature upgrade. While I was at it, I went ahead and uninstalled the Windows 10 Update Assistant as well. All’s clean on that drive now, as far as I can tell.
Author: Ed Tittel
Ed Tittel is a 30-plus-year computer industry veteran. He’s a Princeton and multiple University of Texas graduate who’s worked in IT since 1981 when he started his first programming job. Over the past three decades he’s also worked as a manager, technical evangelist, consultant, trainer, and an expert witness. See his professional bio for all the details.