However, if you are restoring an N800 for a museum, offline demo, or period-accurate experience, here is exactly how it was done back when it worked.
You cannot get a verified, official Facebook Messenger running on a Nokia N800 in 2026. Facebook’s API evolution (Graph API v2.0+), mandatory HTTPS with SHA-256 certificates, and the death of XMPP have made it impossible. facebook messenger for nokia n800 verified