When do I use this proverb "It's an ill wind that blows nobody any good"?

Even misfortune can benefit someone or something.; A calamity for one person usually benefits somebody else. (From Dictionary.com)

Building on @Aethelflaed‘s comment, an example might be a natural disaster. Many people may be affected in a negative way but those who make their living through the building industry will make money repairing and replacing what was lost.

Thanx :D

I think you guys have this backwards. This proverb describes a situation where no one benefits.
Perhaps a good example would be a school shooting, or a distressed parent who killed his childs molester going to jail.
No one wins.

I think the saying is: “It’s an ill wind that blows nobody good.”
Unless you’re talking about an oboe, which is referred to as “An ill wind that nobody blows good.”

John Heywood wrote the first rendition of this in 1546 (The year might be a might off-not sure), which is a negative effect, in it’s strictest sense. Sir Walter Scott alluded to the fact that the ill wind that didn’t do someone some good, would be unusual.
This is my very first post-Thanks mates.

@annewilliams5 Welcome to Fluther! Your first post is very erudite. Thanks. Keep it up.