Cannot log in after a password change in MetaTrader 4

What is causing it

MT4 is still using the old saved password.

Why this happens

MT4 stores the credentials for each account you tick to save, and it uses the stored password automatically on every reconnect. Changing the password in your broker's client area updates it on the server but leaves the terminal holding the old one, so the platform keeps presenting a password the server no longer accepts and the login fails without you having typed anything. This is why the failure appears immediately after a password change and why the platform looks like it is at fault when it is simply doing what it was told.

The same stored credential can also linger across the automatic reconnection that follows a dropped connection, so a session that was working can start failing later without you touching it. Entering the new password through the login dialog replaces the stored one, which is why that step fixes it rather than merely working around it.

The fix, step by step

1. Go to File, Login to Trade Account and enter the new password.
2. Untick "Save account information" if you want to force a fresh login each time.
3. If it still fails, reset the password again in your broker client area.

How to confirm it is fixed

Log in with the new password, then close the terminal completely, reopen it and confirm it reconnects on its own without prompting. That second step is the real test, because it proves the new password was stored rather than just accepted once for the current session.

Stopping it happening again

Log in through the platform with the new password immediately after changing it, rather than waiting until the next reconnect. If you share a computer, consider not saving the password at all, which removes this problem entirely at the cost of typing it each time. Never save credentials on a machine you do not control.