My MT4 is displaying an “Invalid Account” error
With MetaTrader 4, try logging into your account again. There is the possibility that you entered incorrect info on your first attempt- either your account number or your password. If you have any issues with your password, please go back to check the email that was sent to you on your registration.
MetaTrader 4 can be a little tricky when comes to logging in and out. If you've copy pasted your account number (user name) and/or password, make sure you've not copied a "space" before either of them.
This can cause an incorrect password error, a tip is to copy paste your account number (username) and password and paste them into a plain notepad .txt document and then copy them from that into MT4, this way it strips out any special characters that may be copied over from an email styling format or indeed you'll be able to see if there's a space included before or after the account number and password.
Obviously be sure you do not save your account number and password in a plain text document after you've checked your logins.