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It seems this version does not allow you to add custom gateways.

Anyone know how to add gateways on a windows 10 machine without having to add third party clients?

It seems and a few other groups have their own gateways but if you use the gateway editor the install in classic mode still only shows global.

Any ideas?
use newest gateway editor or already edited gateway (with Global gateways). U also can delete any gateways from registry and after that u can have acces to old gateways. Anyway 0 games on any of them, thatnks to Blizz.
download it from or click start, open regedit find \HKEY_CURRENT_USER\Software\\Configuration
and you can see getways