What is the Maximum length that a Windows Registry Key name can be?

Question

I'm writing a very long registry Key name (it's a list of programs for a combined uninstall) and I think it's too big.

What's the max size the key can be (in characters) ? (The smallest maximum among Win xp, vista, 7 since it'll need to work on all of them)

Answer 1

According to this support article, it is 255 characters.