WLM 2009 - Can't log in 80048821 (Windows 10)

Problem description:
New to escargot. Downloaded the recommended version. Patch ran without issue. Software boots but can’t log in. Re-read the get started guide but I can’t see anything daft I’m missing,

Error code/error message:
We can’t sign you in to Windows Live Messenger.
The Windows Live ID or password you entered is incorrect.
Error code: 80048821

What has been tried so far:
Uninstalled/reinstalled (and repatched).
Reset password to an 8 character password.
Changed Internet Properties to only use TLS 1.0

Messenger version:
Recommended - version 2009

Windows version:
Windows 10 Home

Am I just being a dafty and missing something? I’ve done a search but most of the solutions I found seemed to be XP/11 specific issues.

I mean, it’s PPCRL_REQUEST_E_BAD_MEMBER_NAME_OR_PASSWORD (Passport: Invalid email address or password).