Microsoft’s cumulative January 2017 update KB3213986 seems to cause a serious issue in Windows 10 Anniversary Update. After installing this update, system restore fails with error 0x80070091.
I’ve addressed this error within my blog post Windows 10 Version 1607: System restore error 0x80070091 [Fix] a few days ago. Trying to execute a system restore ends after a “long time” with error message 0x80070091.
During investigating this issue, I came to a conclusion, that update KB3213986 is involved. Some of my German readers came back with a comment, that NTFS links within WindowsApps subfolders may be the cause for this issue. One user mentioned VFS sub folders as the root cause (couldn’t be deleted). I searched the web and found some mention of VFS for App-V, desktop brigde and Hyper-V. The changelog for cumulative January 2017 update KB3213986 mentions also fixes in Hyper-V and App-V.
Last weekend I spended several hours to test some things. As a conclusion, I identified KB3213986 as involved into this issue, but It’s not sufficient to uninstall this update to fix the bug. The advices given within my blog post Windows 10 Version 1607: System restore error 0x80070091 [Fix] are still required. At this point I gave up to do further tests (I ran out of time).
But I’ve posted my assumptions within MS Answers forum, and Gegory Livingston confirmed now the following.
- It is update KB3213986 that causes the problem to occur in the first instance.
- Rolling back the update does not correct the problem.
- Performing the known fix returns System Restore functionality.
- For how long, we don’t yet know.
Well, that’s odd. As I wrote within the MS answers forum thread: System restore seems to be terrible broken from time to time; Windows backup isn’t reliable; and I came across forum posts, where restoring Windows 10 using recovery fails also with error 0x80070091. So as a Windows 10 user, you are forced to use a third party backup tool (Macrium reflection, ToDo Backup etc.) to create system backups on a periodical base, in the hope, that you are able to restore a damaged OS. Happy new Windows 10 world – isn’t it?