Something to consider...
Email servers and Outlook work for millions of people every day therefore we know that these parts of the equation work reliably. The most likely place for an error is in the Outlook settings. You may save a lot of frustration by ensuring that the instructions have been followed in detail. Look for spelling mistakes and avoid assumptions.
If you feel that any aspect of our set-up instructions are not clear or explicit, please let us know and we will endeavour to clarify these.