cannot read 'sid' of undefined on linux in windows its working fine

[Warrior-hound]

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[petersaints]

This report is rather uncomplete, but I'm having the same issue.

[lcherone]

Check both client and server versions are the same if you're trying to connect to v3.0.0 server with an older client 2.x.x it wont work

[darrachequesne]

I think you must be trying to connect to a v2 server with a v3 client, which are not compatible.

Since the v2 server doesn't send a sid in the CONNECT packet, it will throw here: https://github.com/socketio/socket.io-client/blob/3.0.0/lib/socket.ts#L227-L229

@Warrior-hound could you please confirm the analysis? Or give additional details about the error? Thanks!

[Warrior-hound]

Thank actually vps installed latest v3 version and so i downgraded it to v2 and it just worked fine. TYSM for help.

[petersaints]

Ok. That seems to be the problem. I wrongly assumed that the new client was backwards compatible with Socket.io v2 server.