Then all he would need to do if he really is using MS Outlook (?), not express, it shouldn't matter as avast is working 'within' the email client and not outside of it, like the Internet Mail provider.
That is why the Internet Mail provider needs to have the redirect ports, where there is no redirect ports within the Outlook/Exchange provider settings.
So essentially if he is using ms outlook and the outlook/exchange provider, then it should work regardless of port, which is why I suggested checking the avast plug-in isn't disabled within Outlook. But we are going to have to wait on iga.
However, he is looking at the Internet Mail provider when he mentions port 110 and 25 as those being redirected and that is totally different to how the Outlook/Exchange provider and the avast plug-in in MS Outlook works.