Question: What happens to MT4 platform when Windows 10 updates?
When windows 10 updates, it may only nullify the saved password.
Thus, you will need to re-type the login credentials to login to your MT4 or MT5 accounts.
Any saved templates or chart settings maybe also lost through this process.
Both MT4 and MT5 trading platforms are compatible with Windows 10 OS.
If you cannot login to your account, you may contact the support team of your broker.