What's the easiest way to view that question, even though it was deleted?
Whoops, sorry, completely missed this part of your question, I was focusing on the title.
slhck's answer is going to be much more helpful on this point.
I think you probably meant What are some "must have" Windows programs? instead.
(the one you link was a dupe of this, and this is the "big" version)
The problem is that it's still a really bad question for the Stack Exchange engine - it's a prime example of a question that matches the Not Constructive close reason. It's a simple poll with no right answer, in fact you can't really justify that any individual answer is even right - Why is Firefox a must have? It isn't; there's plenty of browsers around.
Beyond this, this specific example had devolved in to a list of 321 answers (some of those may have been deleted, so might not all have been visible to users). Almost no one will read all of these, they're only going to read the first few, and who hasn't heard of the top entries: 7zip, Firefox, Chrome, Notepad++, ..? So it's not really that valuable either.
In case you're unfamiliar with it, here's the Not Constructive definition (with my highlights for this case):
This question is not a good fit to our Q&A format. We expect answers to generally involve facts, references, or specific expertise; this question will likely solicit opinion, debate, arguments, polling, or extended discussion.
And if we look at the FAQ, it states:
To prevent your question from being flagged and possibly removed, avoid asking subjective questions where …
- every answer is equally valid: “What’s your favorite ______?”
Basically, the question is a straight up poll and therefore isn't suitable for the site.
The fact it saw a lot of activity in the past (before the rules were properly hammered out) doesn't protect it from closure or deletion and keeping it around is just leaving broken windows for other people to try and use as justification for future bad questions.