Poly~ not seeing my patcher

Aaron Harrison Folb's icon

So my Poly~ is looking for a patcher called Noiser.pat, which does exist, and can be opened, and is in my file search path, but is saying that there's no such patcher. I've tried renaming it but no luck. This used to work fine, but I haven't opened it in a while and now it's not working. I'm in Max 5. Any ideas? Thanks!

Chris Muir's icon

open it directly, then save it as a max 5 .maxpat