Error code 43 in Valorant reads 'There was an error connecting to the platform. Please restart your game client.' Riot classifies it as a connection problem between you and their services, and their first prescription is literal: restart the Riot Client. When that does not cure it, the causes are the Vanguard anti-cheat service not running, network trouble, or a Riot-side incident.
vgc, and start or restart it; set it to Automatic if it is disabled. Vanguard not running produces connection and launch errors.ipconfig /flushdns), and whitelist Valorant and Riot Client in firewall and antivirus.Valorant will not complete its platform connection unless Vanguard, its kernel-level anti-cheat, is present and running. Anything that disables the vgc service, overzealous 'debloat' tools, a failed Vanguard update, a system restore, turns a platform handshake into error 43. That is why a network-sounding error so often ends at a service setting.
Error 43 every single launch, but my internet is fine. That consistency points at Vanguard's service state or a client fault rather than your connection. Check vgc in Services, and if the service is healthy, repair the client by reinstalling it; the pattern matters more than the code here.
Is error 43 a ban? No. Bans and suspensions are announced explicitly in the client with their own notices. Error 43 is a connection failure and says nothing about your account standing.