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New MS Logon = 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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BTJustice
Posts: 5
Joined: 2007-09-13 20:47

New MS Logon = VNC authentication failed!

Post by BTJustice »

I am new to UltraVNC but not to VNC software in general. I have used RealVNC for a few years now and wanted something a bit more secure. So I am giving UltraVNC a shot.

When I configure the New MS Logon and add myself to the user list and try to connect to the remote computer using my username and password for UltraVNC, I keep getting the error message, "VNC authentication failed!". When I turn off the New MS Logon and just enter the VNC password, I connect every time without any problems.

I am not sure what is wrong with the New MS Logon. I tried it again by adding a different user and password and still cannot connect, but if I turn New MS Logon off and use just the VNC password, I can connect every time without any problems.

The added security of New MS Logon attracts me to using UltraVNC. What can I do to make it work?

[mod=494,1189955588]moved from beginner help to MS logon help[/mod]
Last edited by BTJustice on 2007-09-16 15:13, edited 2 times in total.
redge
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Location: Switzerland - Geneva

Re: New MS Logon = VNC authentication failed!

Post by redge »

maybe this help.
[topic=9279][/topic]

you need to use the remote user/password not your local user/password of windows for access the vnc server
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
BTJustice
Posts: 5
Joined: 2007-09-13 20:47

Re: New MS Logon = VNC authentication failed!

Post by BTJustice »

Thanks for the reply. I am not running it as a service. I created a log on name using VNC and use the VNC password. I am not using the Windows XP username/password.
bevtech
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Location: Pennsylvania, United States

Re: New MS Logon = VNC authentication failed!

Post by bevtech »

What operating system are you trying to do this on?
Bevtech

Windows XP Home, Pro SP2, Windows 2003 SBS server SP2(EN), Windows Media Center Editon 2005,Windows Vista Home Prem.,Fedora Core 6,Win9X, PChelpware Rel 1.0,
UVNC V 1.0.8.2

User not developer..;)
BTJustice
Posts: 5
Joined: 2007-09-13 20:47

Re: New MS Logon = VNC authentication failed!

Post by BTJustice »

I use Windows XP Pro and Windows XP Media Center Edition to connect to computers. The computers I connect to are Windows XP Home Edition.
bevtech
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Re: New MS Logon = VNC authentication failed!

Post by bevtech »

Home can not support new mslogon try the standard mslogon or classical authenication and see if it works.


M$ pulled half of the networking features out of home edition hence why it isnt supported..
Bevtech

Windows XP Home, Pro SP2, Windows 2003 SBS server SP2(EN), Windows Media Center Editon 2005,Windows Vista Home Prem.,Fedora Core 6,Win9X, PChelpware Rel 1.0,
UVNC V 1.0.8.2

User not developer..;)
BTJustice
Posts: 5
Joined: 2007-09-13 20:47

Re: New MS Logon = VNC authentication failed!

Post by BTJustice »

Interesting. I wonder what those components are and if they might be available from an XP Pro CD or on the Microsoft website.

The classic logon works fine, but the original MS Logon still won't let me connect.
redge
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Re: New MS Logon = VNC authentication failed!

Post by redge »

http://www.uvnc.com/features/authentication.html
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
BTJustice
Posts: 5
Joined: 2007-09-13 20:47

Re: New MS Logon = VNC authentication failed!

Post by BTJustice »

http://www.uvnc.com/features/authentication.html
So it's important to disable ForceGuest. Otherwise all authorization is done against the guest account!
OK I set it to 0 and it still doesn't appear to work even after a computer reboot.
RanseierK
Posts: 2
Joined: 2008-03-11 08:57

Re: New MS Logon = VNC authentication failed!

Post by RanseierK »

I do have exactly the same problem, but the solution doesn't work

I have a Vista x86 Business PC running the UVNC Server, and i want to connect via the Viewer.

Both Computers are part of an Active Directory 2003, and I tried both MS-Logon methods and the result is always the same "VNC authentication failed !".

The classic UVNC connection worked once but now it fails either.

I read the requierements for the MS-Logon but found no Vista can anyone approve that it works with Vista, and if it does how he realized it.
redge
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Re: New MS Logon = VNC authentication failed!

Post by redge »

vista need uvnc 1.0.4
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
RanseierK
Posts: 2
Joined: 2008-03-11 08:57

Re: New MS Logon = VNC authentication failed!

Post by RanseierK »

I'm using 1.04RC14, meanwhile I even tried to deactivate UAC but without success.
RedSackles
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Joined: 2009-10-05 02:10
Location: Netherlands

Re: New MS Logon = VNC authentication failed!

Post by RedSackles »

i been looking into making a switch from tight vnc to ultravnc because connecting over the internet needed some more security.

now its works wel when using the server password having ms logon disabeld but when i enable ms logon i get the message "VNC authentication failed!" this ocures whith the ultravnc server running as a service on a windows server 2003 platform which is not part of a domain (so standalone server).

ok so what have a tryed to fix this
after going over these boards i tryed the registry setting
HKEY_LOCAL ....Lsa : forceguest
but it was already set to 0 (changing to 1 didnt help so i just changed it back to 0)
i tryed installing it as a server from the ultavnc server progral (right click on the taskbad icon) whith and whithoud the restricted rights box checkt
al also tryed adding the local administrators group to the ms logon as group 1 (schould not be needed since it says the local administrators have acces by default).
tryed restarting the ultravnc service even rebooted te machine between attempts but no succes.

is there a manual to this that i over lookt? most of whats mentiond is in xp not in server 2k3 (they schould work pritty much similar specialy since its local users authenticating)

i know this might not seem like a big deal, one could say vnc works with its native authentication so why bother. but of from a security standpoint it would be benificial to use ms logon as a aditional layer of security.
Last edited by RedSackles on 2009-10-05 02:30, edited 1 time in total.
YY
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Re: New MS Logon = VNC authentication failed!

Post by YY »

RedSackles wrote:now its works wel when using the server password having ms logon disabeld but when i enable ms logon i get the message "VNC authentication failed!"
At the window of “MS Logon setup”, it mentioned that “Local admins have always access”, but I found there is a bug in this setting:
Image

If all the entry of the three groups are empty, the server will reject any connection.

On the other hand, if any one of the box has something enetered – EVEN IF NOT A VALID GROUP NAME, the server can accept local administrators group to logon (work as expected).

I found this problem since 1.0.2 & upto the latest 1.0.6.5, and even the beta 1.0.7.x, tested on WinXP system.
Last edited by YY on 2010-08-11 04:34, edited 1 time in total.
RedSackles
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Joined: 2009-10-05 02:10
Location: Netherlands

Re: New MS Logon = VNC authentication failed!

Post by RedSackles »

i attemted your suggestion but after putting in the username and password of the local administrator i still get the same message "VNC authentication failed!"
adding the local administrators group or a vnc user group (a group i made) or a none existing group dont seem to change this.
Pakito
Posts: 2
Joined: 2009-12-17 07:47

Re: New MS Logon = VNC authentication failed!

Post by Pakito »

YY wrote:
RedSackles wrote:now its works wel when using the server password having ms logon disabeld but when i enable ms logon i get the message "VNC authentication failed!"
At the window of “MS Logon setup”, it mentioned that “Local admins have always access”, but I found there is a bug in this setting:
Image

If all the entry of the three groups are empty, the server will reject any connection.

On the other hand, if any one of the box has something enetered – EVEN IF NOT A VALID GROUP NAME, the server can accept local administrators group to logon (work as expected).

I found this problem since 1.0.2 & upto the latest 1.0.6.5, and even the beta 1.0.7.x, tested on WinXP system.
Spot on!! After trying different things, this worked like a charm!
paul1149
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Re: New MS Logon = VNC authentication failed!

Post by paul1149 »

I'm getting the same error here, with both new and old MS Logon. I'm trying to reverse-connect an XP server to a Win7 client, both on the same intranet through a router, and not getting anywhere. Using simple uVNC password works smoothly.

The error message gives several possibilities, but I think I've got them all covered, so it must be an MS Logon problem. Too bad, because the increased security is very desirable.

p.
YY
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Re: New MS Logon = VNC authentication failed!

Post by YY »

paul1149 wrote:I'm getting the same error here, with both new and old MS Logon. I'm trying to reverse-connect an XP server to a Win7 client, both on the same intranet through a router, and not getting anywhere. Using simple uVNC password works smoothly.
I don't understand.

In reverse connection, there is no authentication, i.e. use neither VNC password, nor MS Logon user+password.

So what is your problem, and what error message did you get?
paul1149
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Re: New MS Logon = VNC authentication failed!

Post by paul1149 »

I got what seems to be the omnibus error message, citing that the connection failed and offering about six possible reasons why.

Interesting about the reverse connection not needing authentication. I didn't know that. For some reason, speccing MS Logon, whether old or new, is the make or break for connection.
YY
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Re: New MS Logon = VNC authentication failed!

Post by YY »

Sorry but I'm still not able to catch. :|

What is omnibus?


paul1149 wrote:Interesting about the reverse connection not needing authentication. I didn't know that. For some reason, speccing MS Logon, whether old or new, is the make or break for connection.
How did you produce the error message?

MS Logon (old or new) + Normal connection ===> error message ?, or

MS Logon (old or new) + Reverse connection ===> error message ?



And what is the actual error message you got?
paul1149
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Re: New MS Logon = VNC authentication failed!

Post by paul1149 »

Omnibus:
adj
(prenominal) of, dealing with, or providing for many different things or cases
[from Latin, literally: for all, from omnis all]

I was attempting a reverse connection.
YY
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Re: New MS Logon = VNC authentication failed!

Post by YY »

Thanks for the explanation.

If you got the message of "VNC authentication failed!" in reverse connection ONLY with using MS logon but NOT using simple uVNC, then I really be surprised.

For the best I know, there is no authentication with reverse connection in both situation.

If you can provide more detail of your config. and the testing environment, may be the developer or other experienced users can give a better advise.
paul1149
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Re: New MS Logon = VNC authentication failed!

Post by paul1149 »

That's exactly what I think happened, but I'm not sure when I'll be able to verify, as the other box is not receiving AC power at the moment.
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