Determines whether the RPC protocol messagese used by VSS for SMB2 File Shares feature is enabled. VSS for SMB2 File Shares feature enables VSS aware backup applications to perform application consistent backup and restore of VSS aware applications storing data on SMB2 File Shares. By default the RPC protocol message between File Server VSS provider and File Server VSS Agent is signed but not encrypted. Note: To make changes to this setting effective you must restart Volume Shadow Copy (VSS) Service .
HKEY_LOCAL_MACHINE -> Software -> Policies -> Microsoft -> Windows -> fssProv # EncryptProtocol
System -> File Share Shadow Copy Provider