Is this logic sound, if not, what is the error called?

Statements of the form “P or not P”, where P is a statement that is either true or false, are called “tautologies” in formal logic. Their truth value is not based on the content of P (knowing whether P is true or will be true i the real world), but based totally on the formal structure of the sentence “P or not P”.    Therefore, this has nothing to do with foreknowledge.  The fact that we’re talking about something in the future is irrelevant.  

If you buy a lottery ticket, then either you will win, or you will not win. 

This is not a statement about the future, and so knowing it does not constitute knowing the future. It just lays out a condition.

Shawn’s comments against Fred are quite interesting, but not addressed at what I defended, to be sure. I did not argue that knowing that  if you buy a lottery ticket, then either you will win, or you will not win constitutes a logically possible case of foreknowledge. Also, should Shawn think that my belief that foreknowledge is logically possible is unjustified, he shall have to address my argument, rather than sounding sure of his criticism while at the same time showing no mistake in my argument. I am reminded that is unfortunately common in the Internet age to find people who strongly criticize beliefs, but do not evaluate the arguments given for the beliefs. I am also reminded that it is common to find people who don’t really know what they are talking about, such as people who think that I’m Fred but don’t recognize that Fred’s argument is not my argument. (Let me go ahead and explicitly note that my impression is that Shawn’s last post was alluding to me.)

Ed F has interesting comments to make about Fred, but thankfully I’m not truly Fred. Fred does not give the argument that I gave. 

Rationalissimus makes points that are so interesting that I am relieved that Fred, instead of me, is on the receiving end of them. For I did not argue that a lottery ticket will either be a winning one or a losing one  constitutes a logically possible case of foreknowledge. Nor does Rationalissimus give any reason to think it plausible that foreknowledge is limited to events. Nor is he speaking plausibly. If I know that the White House will be eight stories tall in the year 2066, surely that is foreknowledge. But the White House’s being eight stories tall in 2066 is not an event. 

So, my answer is that Fred’s logic is quite questionable, for reasons others have pointed out and for the reason that I pointed out at the top of my Answer. Also that, of course, I am glad to not be in Fred’s shoes. 

Also, I took a look at the thread and noticed that you asserted “If the only future outcomes are [A] and [not A], then stating that as foreknowledge is perfectly logical and there is no contradiction involved.”

So, are you intended to be Fred or am I? 

Fred says "I have foreknowledge, because I know that a lottery ticket will either be a winning one or a losing one." 

But that doesn't demonstrate knowledge of an event (actually winning or losing) before it happens. That's stating a fact of probability. 

It's like saying, "if you flip a coin, it'll either be heads or tails." Yeah, we know. That isn't describing an event (which would be the coin actually landing on either side).

If a person knew which side specifically the coin would land on before it was tossed, that would be foreknowledge. It'd be a revelation of something hitherto unseen. 

The key with foreknowledge is that the event has to be in the future. It can't be a present fact.