So, I've been trying to get a cursed halo LAN game going between my roommates and I using the instructions here at https://www.patreon.com/posts/32142430, but i keep getting a cd invalid error when I try to join. So i'm wonder where the best place is to buy a few working ones?

You'll need different CD keys if you want to play together, though I'm pretty sure HAC2 fixes that
If you're looking to buy a CD key you can look for a copy of Combat Evolved PC on Amazon, but let's be real, 99.9% of CE players are dirty criminal pirates (not that I'm encouraging you to be one too )

You'd just have to buy used from Amazon or Ebay. Not a lot of legit places will have a new copy unless its pricey

It's at your own discretion to go either way.

A fully upgraded haloCE client with today's luxuries(hac2//chimera 1.0) doesn't actually do CD-key verification anymore.
Either way, there's not a single soul in the custom edition playerbase or dev community that will fault you for it and modern servers use other methods for player identification anyways, it's a given that you won't find an 'untouched' new copy in 2020.

Edited by OrangeJuice on Apr 21, 2020 at 01:09 AM

I'd say if one wishes to make there feelings feel better about it buy H1 on the MCC on PC.
good old Microsoft could always use more $$ anyway.