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VNC authentication failed

Should you have problems with the MS logon plugin, here's the place to look for help or report issues
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MichHK
Posts: 4
Joined: 2006-03-31 09:07

VNC authentication failed

Post by MichHK »

I get this message with every user. I have configured New MS Logon. Both PC's use Windows XP Prof. Login directly on the pc is working right. But with Viewer i get always this message.

A UVNC password is set. On firewal there are all ports 80, 5800 and 5900 open. The configuration must be right, because i get the login window. On another pc the same configuration is working very well. On all pc's UVNC is working as service.

I type in the window username and password, right like the normal login of the pc. Always this error. At last the pc is starting again. Nothing is changed.

I could not find any answer for this. Could someone help me?
redge
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1000
Posts: 6797
Joined: 2004-07-03 17:05
Location: Switzerland - Geneva

Post by redge »

vnc server admin properties
complete field VNC password even you not use VNC authentication but only Require MS-Logon
- New MS Logon

please read again UltraVNC Authentication
http://doc.uvnc.net/features/authentication.html
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
MichHK
Posts: 4
Joined: 2006-03-31 09:07

Post by MichHK »

Thank you for the request. Yes, i had set a password in field VNC password.
redge
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1000
Posts: 6797
Joined: 2004-07-03 17:05
Location: Switzerland - Geneva

Post by redge »

Under Windows XP, the ForceGuest registry value is set to 1 by default in the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa

On a Windows XP computer you must check:
If the Guest account is enabled, an SSPI logon will succeed as Guest for any user credentials.
If ForceGuest is disabled (set to 0), SSPI will log on as the specified user.
If the authtest util gives guest account blocked, an open guest account is detected and ms logon denies all access.
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
MichHK
Posts: 4
Joined: 2006-03-31 09:07

Post by MichHK »

Thank you, i will check this on monday, because the server is not near my home.

I have checked this on my working server. If ForceGuest is set to enabled, i get a authentication failed. I hope this is the reason.
Last edited by MichHK on 2006-04-01 21:17, edited 1 time in total.
MichHK
Posts: 4
Joined: 2006-03-31 09:07

Post by MichHK »

Thank you very much. I change ForceGuest to disabled. Now i can login as the specified user.

Why does this happen? On both pc's there is guest disabled. But by one pc ForceGuest is disabled and by the other enabled. The first working pc, there are two user defined, the other only one user. Could this be the reason?

Is ForceGuest set by windows or UltraVNC?
redge
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1000
Posts: 6797
Joined: 2004-07-03 17:05
Location: Switzerland - Geneva

Post by redge »

Is ForceGuest set by windows or UltraVNC?
by windows
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
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