So, my question is actually quite simple: I'd like to remotely connect to a PC with UltraVNC 1.6.4.0 running as a service under Windows 10 22H2,
The trouble is that I'm using a Mac (currently a MacBook Pro with an Apple M1 Pro CPU, running macOS Tahoe 26.2) — I could use the Java version of UltraVNC locally, but I hate to install the whole Java runtime — it weighs down even pretty decent hardware, and is almost impossible to fully uninstall afterwards. So, thank you — but no.
Since UltraVNC is allegedly fully compatible with the RFB protocol, I wouldn't expect many 'compatibility issues' when connecting with so-called 'standard' settings. The trouble is to figure out what the 'standard settings' are!
Basic things first: aye, I have connectivity, and the UltraVNC service is really running on port 5900. To prove it, I just do a simple nc IP-address-of-PC 5900, and, as expected, it returns something such as RFB. So far, so good.
Next, I've attempted connecting with the macOS VNC client, called Screen Sharing.app. Apple has always used RFB, and I usually have no problem connecting to other machines (all running some Linux distro). However, the PC running UltraVNC seems not to like whatever data the Mac is sending to it; it always returns a connection error, almost always with some sort of 'authorisation problem' (I checked and re-checked and I'm really, really using the correct password (which has 10 characters — is that a problem?).
Then I tried TigerVNC, which also has a native Mac implementation of a VNC client. The problem is probably not the same — the configuration is different, with additional options missing on UltraVNC, and vice-versa — but error messages such as 'failed to connect' or 'server refuses to connect' are frequent.
My best guess, therefore, is that there is some missing configuration that has to be precisely matched at both ends, or nothing will work; my question, therefore, is what parameters should be set, or what should I be looking for on each end — RFB has so many extensions, some of which everybody takes for granted (until they don't work), and I'm at a loss to figure out what settings are required at each of the endpoints.
Can someone give me some pointers?
Thanks in advance
. They must have done something special to the way they handle RFB connections, since it works beautifully. No issues with display sizes and so forth. Whatever protocol they are using, it gets properly negotiated with UltraVNC, which accepts the configuration parameters flawlessly. It's a truly fantastic experience. I noticed that the actual resizing to fit everything properly on the Mac's side is done locally; that is, it automagically gets the data sent by UltraVNC and uses the Apple magic libraries to do the rescaling-on-the-fly without missing a single frame, making the experience super smooth — even if connected to more than one session. No slowing down whatsoever.
