ZSNES's netplay feature was removed in the most recent versions. v1.42 is the version most commonly used for netplay now.
Keep in mind that programs like these can't add any extra functionality to ZSNES itself, like for example, the often asked about ability to use 3 or more players all from different computers. They simply connect 2 users and load a game.
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Z-Net I
- This program was originally designed as an exact clone of zbattle, to replace it after it went offline. But it's key difference is using IRC as its backbone, which means it won't go offline easily.
This service is not owned and maintained by the ZSNES developers. Please, before posting troubleshooting related issues with a service like this, first be sure to check it's respective forums/FAQs/manuals. Also be aware that this service may be down at unpredictable times. Unfortunately, we have no control over this.