Here's why it's unlikely to find definitive information about the Harry Potter cast's use of MSN:
* Privacy: Celebrities' personal online activities are typically private. There's no publicly available information about their specific messaging platform use.
* Time: MSN was popular during the early 2000s, but its use declined as newer platforms like Facebook, Twitter, and Instagram emerged. By the time the later Harry Potter movies came out, MSN was less prevalent.
* Cast Size: The Harry Potter cast is large and includes actors of various ages. It's impossible to say if every cast member used MSN, and it's unlikely they all did.
So, while it's conceivable that some of the cast members used MSN, it's not something that can be confirmed or widely known.