Someone might be able to take a stab at it if you were to actually share what the error message says (Verbatim please)

What I am trying to illustrate clearly that we only know what you share and to be honest you have stated the problem you have, but have shared nothing on which anyone might form a guess even. Like we know Cox is migrating to yahoo. But is that your provider? We know there have been issues with Kaspersky antivirus in the past, but do you use it or something else.