Rescue Disk creation impacts VSS - solution

[GregLauver]

This post is informational.  This issue has existed for Kaspersky Rescue Disk v10 and v18 in Windows 10.  It causes Volume Shadow Storage based operations, such as backups in Acronis True Image and Windows System Restore, to fail.  When creating a KRD on a USB flash drive, essential upper filter(s) "volsnap" (and "fltsrv") are removed from the Windows Registry key

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{71a27cdd-812a-11d0-bec7-08002be2092f}

replacing them with Kaspersky's filter "klbackupdisk".  Adding those filters back into the value "UpperFilters" restores VSS functionality:

"UpperFilters    REG_MULTI_SZ    klbackupdisk volsnap fltsrv"

I originally found this solution in an obscure post at Sysnative Forums which specifically named KRD as a common cause.  Acronis Help now lists the same solution without mentioning KRD.  Again, this message is only informational because I fixed the issue via Regedit.

[Yury N.]

Hello.

Looks like you're wrong. KRD doesn’t create filters. KRD cleans incorrect filters of other Kaspersky products https://support.kaspersky.com/14221

[GregLauver]

It looks like you’re right.  With no other activities, I created a new KRD, then checked the Windows Registry, and the UpperFilters remained unchanged.  On a hunch, I searched

Google> volsnap site:acronis.com

and found agreement in the Acronis Forum that un/installing Acronis products can remove those UpperFilters values with various bad effects.  I now believe I had also updated Acronis near the same times as I updated Kaspersky and created new KRDs.

Because this thread could appear in search results and add to confusion, it should be deleted.