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When connecting and entering the Windows login password, the session is dropped.

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izm
Posts: 1
Joined: 2023-06-13 06:38

When connecting and entering the Windows login password, the session is dropped.

Post by izm »

【Symptoms】
When connecting and entering the Windows login password, the session is dropped.
ーーーーーーーーーーーーーーーーーーーーーーーー
Version 1.4.2.0 is being used.
The connection itself works after entering the VNC password, and the Windows login screen is displayed.
However, when entering the Windows login password, the message "Connection dropped, trying to reconnect" is shown, and the session is terminated.
I have uninstalled and reinstalled the software twice, but the same issue persists only on a specific remote PC (referred to as "A").
The configuration settings are the same as other devices that work correctly.
(There are 2-3 other devices with the same setup in the same location and using the same network connection, but they do not experience this behavior.)

Furthermore, not only myself but other users also cannot connect to PC "A" due to the same issue.

PC "A" itself has Windows Remote Desktop settings configured, and it seems to work fine without any network-related issues.

VNC was first set up on PC "A" in late May 2023, and it was able to connect without any problems at that time.

User Account Control is set to "Notify me only when apps try to make changes to my computer (do not dim my desktop)."
Private network is used.
During the software installation, "Start or restart UltraVNC service" was enabled.

【Points of Concern】

When connecting with VNC, the Windows screen is displayed at about 1/4 of its total size.
Even when maximizing the window or setting the resolution correctly, the remote PC does not display in full screen.
Reinstalling the software or restarting the PC does not resolve this issue.
Additionally, other users besides myself experience the same behavior.

On other remote PCs where the connection works properly,
the Ultra VNC Server icon in the system tray appears golden, and the right-click menu shows the "Start Service (must be installed first)" option grayed out.
However, on the PC that cannot establish a connection, the icon is cyan.
Clicking "Start Service (must be installed first)" multiple times does not activate it.
Furthermore, after clicking "Start Service (must be installed first)", the UltraVNC Server shuts down on its own.
It reappears in the system tray when relaunched.
ーーーーーーーーーーーーーーーーーーーーーーーー
If there are any parts that are unclear in the translation I provided, please let me know. :cry:
3D-Admin
Posts: 3
Joined: 2023-08-16 09:22

Re: When connecting and entering the Windows login password, the session is dropped.

Post by 3D-Admin »

Hi, I have a similar problem and the cause is a KVM switch (which connects two PCs with a monitor, mouse and keyboard).
When the switch is on the other PC turned off, the behavior occurs.
If the switch is switched, the error is gone.
Maybe this helps you with troubleshooting.
Last edited by 3D-Admin on 2023-08-17 09:15, edited 1 time in total.
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Rudi De Vos
Admin & Developer
Admin & Developer
Posts: 6838
Joined: 2004-04-23 10:21
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Re: When connecting and entering the Windows login password, the session is dropped.

Post by Rudi De Vos »

There are reports that some headless systems cause trouble.
In the past a headless system still had some grahics card active, and vnc could clone it.
Now some systems report a random screen size confusing vnc.

Some people use the virtual display driver we included or a dummy screen connector.
In both cases the pc think a screen is connected and keeps the graphics active.
RDP has his own graphics, so is works without an issue on a headless system.
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