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Has anyone been able to log into the GOG gateway using the original retail cd version of Diablo?
I've added the GoG gateway in the registry and forwarded ports/made firewall rule/ and other typical troubleshooting measures and I can't get it to work.

Even though I'm at patch 1.09, if I try to log in, it'll say that it's going to download a new patch and then give me the error that it can't apply it to the file battle.snp.

Is there a way to get it to work or do I have to buy the GoG version?
This question / problem has been solved by .Astral.image
Check out this article on D1Legit...

It goes through all the steps to help you do exactly what you are looking to do:

Keep in mind they advocate 1.09b but I believe the same can work with 1.09 as well.
Edit: Deleted
Post edited July 13, 2019 by hoogiboo
It worked. I'm an idiot. Thanks.