For those that were reading the post of @Guaranteed Profits and...

For those that were reading the post of @Guaranteed Profits and missing the context, you can only short shares that are available to borrow.
That is to say, you cannot sell shares you do not own, so to short sell you must borrow the shares from someone who does own them.
This adds a whole other complexity when there is no contracted time frame for the loan of said shares.

But in the context of the post there was nothing available to "borrow" hence there were no shares available to short sell.
You cannot sell shares that do not exist.
You sell your borrowed shares with the intention of buying them back cheaper before returning them to their owner.

Probably not as clear as it could be, but then I'm just your average old fella with a beard.