The Windows version of the prebuilt binary for 1.2.1 is signed with a SHA256 certificate, but the file digest algorithm of the signature is still SHA1. Likewise, so is the timestamp digest algorithm.
It appears that the latest build of Windows 10 (on the fast ring) no longer allows signatures where the file digest algorithm is SHA1, causing it to warn that the signature is invalid.
Regardless of whether or not this change reaches Windows stable, I'd recommend re-releasing this with a dual SHA1 / SHA256 signature.
The Windows version of the prebuilt binary for 1.2.1 is signed with a SHA256 certificate, but the file digest algorithm of the signature is still SHA1. Likewise, so is the timestamp digest algorithm.
It appears that the latest build of Windows 10 (on the fast ring) no longer allows signatures where the file digest algorithm is SHA1, causing it to warn that the signature is invalid.
Regardless of whether or not this change reaches Windows stable, I'd recommend re-releasing this with a dual SHA1 / SHA256 signature.