WireGuard Windows should have default MTU of 1280.

[Michael Tokarev]

21.02.2022 22:11, Michael Adams wrote:
> Throwing in my two cents: I was using MTU 1280 on Tinc a few years back, for IPv6 VPN support on Windows & Linux. It's good practice.

Lemme guess. The OP is routing wg packets over IPv6?  Can this be
the problem here, because V6 has larger overhead so that 1420 is
too large to fit into 1500 bytes together with IPv6 header?

Speaking of the good practice - it really depends.

/mjt