“Questions”
Non gov emails could be blocked but they don’t. They do use spam blockers, but that usually results in items being sent to a “junk” folder, which can still be accessed.
What is typically done is blocking access FROM the government system TO an email server itself (which is not the same as preventing mail from being sent to a non gov address).
E.g., if you have a gov laptop, it will block you from logging into your Yahoo mail account. This is because they don’t want the government network exposed over that connection. Simply sending an email doesn’t do that so there is no problem in just sending / receiving mail from private systems (though you still have to worry about viruses and hostile links so they tell you to delete unrecognized senders).
Incidentally, this is why Hillary would need two devices to use private and gov email. I’ve heard folks in the news talking about how easy it is to access two different email accounts from one device, but they are obviously unaware of the gov restriction on that.
Non gov emails could be blocked but they don’t. They do use spam blockers, but that usually results in items being sent to a “junk” folder, which can still be accessed.
So, shortly after taking office it is very likely that Hillary had to follow-up her e-mails to .gov, including ones to 0bama, with a phone call saying “I sent you an email?,,, Check your spam folder”