Hi there,
Just wondering if there was any way to troubleshoot this.
So I have a device, when I VNC into it it works great. Then if say I disconnect, and attempt to connect again - my viewer just completely hangs and I have to kill the app.
Is this an issue anyone else has had, or is there anyway I can troubleshoot this? I know it is not an issue with my device as I get the same problem using another device to connect to it, and other machines connect fine.
Any help appreciated, thanks.
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UltraVNC does not connect when connecting second time
- Rudi De Vos
- Admin & Developer

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Re: UltraVNC does not connect when connecting second time
If you disconnect and reconnect fast, the server didn't have time to reset and you connect while the port isn't open.
The viewer only get notified after a connect timeout and this timeout is long... can be a few minutes.
The viewer only get notified after a connect timeout and this timeout is long... can be a few minutes.
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Re: UltraVNC does not connect when connecting second time
Hi Rudi,
Thanks for the reply, however it can sometimes take up to 30 minutes to reconnect again. I have tested this on another device in another network and the time between re connection is done incredibly quickly - say 20 - 30 seconds.
Is there anything else I should be aware of that could be impacting this, such as network issues etc?
Thanks for the reply, however it can sometimes take up to 30 minutes to reconnect again. I have tested this on another device in another network and the time between re connection is done incredibly quickly - say 20 - 30 seconds.
Is there anything else I should be aware of that could be impacting this, such as network issues etc?
- Rudi De Vos
- Admin & Developer

- Posts: 6978
- Joined: 2004-04-23 10:21
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Re: UltraVNC does not connect when connecting second time
We need to know the status if the server, this isn't a viewer thing.
It's like when a browser fail to connect to a website... usual it isn't a browser problem, but a netword or webserver issue.
Is vnc server still runnning after disconnect?
Color of the trayicon after you disconnect the viewer
Are you running as service/app
ultravnc.ini server ( erase passwd)
Activate the winvnc.log
It's like when a browser fail to connect to a website... usual it isn't a browser problem, but a netword or webserver issue.
Is vnc server still runnning after disconnect?
Color of the trayicon after you disconnect the viewer
Are you running as service/app
ultravnc.ini server ( erase passwd)
Activate the winvnc.log
UltraVNC links (join us on social networks):
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- Forum: https://forum.uvnc.com/
- GitHub sourcecode: https://github.com/ultravnc/UltraVNC
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- Bluesky/AT Protocol: https://bsky.app/profile/ultravnc.bsky.social
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- Reddit community: https://www.reddit.com/r/ultravnc
- OpenHub: https://openhub.net/p/ultravnc
- uvnc2me: https://uvnc2me.com/
- Website: https://uvnc.com/
- Forum: https://forum.uvnc.com/
- GitHub sourcecode: https://github.com/ultravnc/UltraVNC
- Mastodon: https://mastodon.social/@ultravnc
- Bluesky/AT Protocol: https://bsky.app/profile/ultravnc.bsky.social
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