Why isn't MT4 working?
Take a look at the bottom right of the platform. If you see a message such as ‘invalid account’ or ‘no connection’, check your login details and try to log in again. Remember to use your MT4 details, not your normal tastyfx details – you’ll have a five or six-digit account number for MT4.
Also check the server you are logging in to. If you are using a live account, you’ll need to select ‘IG-LIVE’ from the server drop-down menu in the login window. You can also type in the address manually: mt4.ig.com:443.