SMB 2.2 durable handles fallback to SMB 2.1 behavior on Windows 8 clients

Determine whether a Windows 8 client will automatically disable durable handles and revert to non‑durable SMB 2.1 semantics when the server advertises only SMB 2.1, and how this affects write retry safety.

The documentation states that durable handles are enabled by default for SMB 2.2 connections but does not specify the client‑side fallback logic when the negotiated dialect is lower than 2.2. This leaves uncertainty about whether the client treats the connection as non‑durable, attempts to emulate durability, or applies a different timeout/retry scheme.

• What does the Windows 8 client do with durable handle state when connecting to an SMB 2.1‑only server?
• Does the fallback automatically disable durable handles, and if so, is this behavior configurable?
• How does the fallback impact the likelihood of duplicate writes on brief network interruptions?