Issues with HOTMAIL Accounts

We can't find any official policy against Hotmail, however, this was the second time in a week I found emails from  students using Hotmail accounts in the spam folder.  I heard other colleagues said they observe the same.  I assume it was some spam lists the College IT department subscribes to.  We can't move the mountain, so the advice is to use non-Hotmail account when you are writing to a Hood faculty.