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MSRC4 + SC Failure

Should you have problems with the DSM plugin, here's the place to look for help or report issues
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beporter
Posts: 4
Joined: 2007-02-12 18:18

MSRC4 + SC Failure

Post by beporter »

Using:

UltraVNC v1.0.2
SingleClick REL 1.00
MSRC4Plugin v1.1.8, 1.2.0, 1.2.2

Quick run down of things I've already read about in the forums:

* MSRC4Plugin.dsm (renamed from MSRC4Plugin_NoReg.dsm) is in [tt]"C:\Program Files\UltraVNC\"[/tt]

* rc4.key is also in [tt]"C:\Program Files\UltraVNC\"[/tt] (The plugin is finding the key correctly according to the config screen.)

* Vncviewer started using: [tt]"C:\Program Files\UltraVNC\vncviewer.exe" -listen 5501 -dsmplugin MSRC4Plugin.dsm[/tt] (The plugin is loading correctly and I can view the config screen for it.)

* rc4.key was included when building sc.exe (Same key used in the viewer directory, obviously.)

* helpdesk.txt contains:
[tt]
[host]
Helpdesk - Clear
-connect 1.2.3.4:5501 -noregistry

Helpdesk - Encrypted
-plugin -connect 1.2.3.4:5501 -noregistry
[/tt]

* There are no software firewalls on the viewer machine blocking the connection. (Proven by the fact that the non-excrypted connection "Helpdesk - Clear" works superbly.)

* Client and Server machines are both XP Pro, so no Win2K issues here.


Okay, all that said, the actual problem is that the encrypted connection just hangs when started from the SingleClick client. The vncviewer.exe just freezes, but there's no error. Only killing the SC server "unlocks" the vncviewer program again. At that point, the error is "Error reading Protocol Version". I've tried 3 different versions of the MSRC4Plugin (1.1.8, 1.2.0, 1.2.2) and none of them work. Remember, the unecrypted connection between the same two computers works fine, so this has to be a problem with the MSRC4 plugin somwhere.

The question is: what in the heck did I miss?
beporter
Posts: 4
Joined: 2007-02-12 18:18

Re: MSRC4 + SC Failure

Post by beporter »

Additional Info:

The existing listener successfully accepts a "pushed" connection from a full UVNC server with the plugin and key loaded. That would seem to imply that whatever is wrong is wrong with the SingleClick exe generator, wouldn't it?
tiwae
Posts: 4
Joined: 2007-01-30 20:16
Location: Jurassic

Re: MSRC4 + SC Failure

Post by tiwae »

I had the same ploblem with SC and the Plugin. Try this :

When UVNC is installed on the server machine, you must copy the plugin in the uvnc installation directory.
:wink:
SRNET
Posts: 2
Joined: 2007-02-19 10:22

Re: MSRC4 + SC Failure

Post by SRNET »

Well, I have exactly the same problem.

I have created an SC that has several connections, some encrypted, some not. SC finds the 'viewer' by DNS lookup.

The PC running VNC viewer is a Windows XP, that running the SC is a Windows 2003 server. The PC running SC has no UVNC software installed and no ORL reg keys.

All the non - encrypted connections work, but none of the encrypted ones do.

Nothing happens on the viewer (its in listen mode) until the SC connection is closed, and then I get the invalid protolcol message.

Using the latest DSM plugin, same key on viewer and SC etc.
beporter
Posts: 4
Joined: 2007-02-12 18:18

Re: MSRC4 + SC Failure

Post by beporter »

Just a couple of extra points:

* MSRC4Plugin.dsm IS in my UVNC folder.

* You should try not to use DNS hostnames in your SC heldesk.txt file. There is a (very) outside chance that the computer that runs the SingleClick server has had its DNS poisoned and your pushed VNC connection attempt could be sent to someone else entirely. Whenever possible the safest possible choice is to use hardcoded IP addresses.


Now, does anybody have any additional ideas? I think we need to talk to whoever wrote the online SC generator since it's obviously not producing executables that work correctly with encryption. Anyone know who's in charge of maintaining the online generator?
SRNET
Posts: 2
Joined: 2007-02-19 10:22

Re: MSRC4 + SC Failure

Post by SRNET »

I am aware that someone COULD hijack the DNS, but its unlikley to be a problem in our closed network. The hijacker would also need to get hold of the key file.

The reason for using DNS is that the support PCs could change over time, and its easier to change DNS than the SC executable.

One thing that I am looking at is getting the executable on a web page somewhere, in which case it would be possible to change the source file for SC every time a support PC changed.

I was wondering about the SC compiler myself, I am almost sure I had this working several days ago, but after getting it SC working in basic mode I started adding connections for the repeater option. The repeater option works (non encrypted) but since Friday I have been unable to get the SC Encryption setup working even in direct mode.

But here is something interesting.

This morning I checked carefully that I had the right keys and plugin versions for SC and the viewer. The compiled SC would not connect using encryption mode.

This afternoon I gave the SC compile another go. Same key and plugin files as this morning. The only change I made was to add some more connections and changed the title text in helpdesk.txt etc.

Guess what ? My compiled SC now works !

So I have two versions of SC, one compiled this morning that does not work and one complied this afternoon that does.
kuriharu
Posts: 7
Joined: 2007-03-02 20:01

Re: MSRC4 + SC Failure

Post by kuriharu »

I'm in exactly the same situation as all of you.

I've followed 3 guides step by step that say how to do this, and it still doesn't work. Non-encrypted works like a dream, but anything encrypted just locks up VNCViewer until I kill the remote attempted connection.

Hope somebody has a solution, as I need to use this in a hospital.
kuriharu
Posts: 7
Joined: 2007-03-02 20:01

Re: MSRC4 + SC Failure

Post by kuriharu »

I managed to get it to work. I can't believe it!

It works great and it's using the encryption module. Pretty slick.
UltraSam
Admin & Developer
Admin & Developer
Posts: 462
Joined: 2004-04-26 20:55
Contact:

Re: MSRC4 + SC Failure

Post by UltraSam »

Can you share with us what was the problem and how you solved it ?

It's always good to enrich the troubleshooting knowledge base ;)
UltraSam
kuriharu
Posts: 7
Joined: 2007-03-02 20:01

Re: MSRC4 + SC Failure

Post by kuriharu »

Absolutely. Working on a short write up right now. Should have it posted in a couple of hours. I'm at work or I'd have it now.
kuriharu
Posts: 7
Joined: 2007-03-02 20:01

Re: MSRC4 + SC Failure

Post by kuriharu »

Sorry, I lost my notes on what I did, but here's the trick that got it to work:

When I set up my .zip file for upload, I included the same MSRC4Plugin.dsm in that zip file that was in my c:\program files\ultravnc directory. I also made sure the helpdesk.txt file had the -noplugin line, as I re-installed the custom.zip and accidentally re-created the generic helpdesk.txt without it.

Once I had that and a matching rc4.key file, it worked. Don't know what I was doing wrong so many times, but this seemed to do it.
canoodle
Posts: 1
Joined: 2007-04-29 12:48
Contact:

Re: MSRC4 + SC Failure

Post by canoodle »

hi folks!
first of all i wanna thank the staff thanks for the great programm!

got the exactly same problem...
to add to all of this confusion...

also did everything like kuriharu

i get a encrypted connection... for a few seconds...

THAN CLIENT freezes... AND I CAN NOT EVEN ACCESS THE INTERNET ANYMORE FROM THE LISTENING CLIENT! (IN FACT, ALL THE NETWORK TRAFFIC IS SOMEHOW DOWN/BLOCKED... WINDOWS NETWORK STALLED... NETBIOS, LAN, DHCP... EVERYTHING)
i think it seriously interferes with some windof svchost.exe network stuff...
i am not that low-level skilled to analyse the problem further...

client and server are on the same intranet (for testing) but the traffic goes through internet dyndns & so on...

un-encrypted things work right!
LOL

i tried every plugin
MSRC4Plugin.dsm
MSRC4Plugin_NoReg.dsm (because there is this -noregistry switch in the helpdesk.txt)
AESV2Plugin.dsm


i got outpost firewall... but it works with unencrypted so this should not be a problem

both client and server are under win xp sp 1 v 5.1. build 2600
archiboy
Posts: 2
Joined: 2007-06-09 09:33

Re: MSRC4 + SC Failure

Post by archiboy »

Here is what I have noticed about the MSRC4Plugin.dsm (as well as the MSRC4Plugin_NoReg.dsm version)...

If I use a DNS name in my helpdesk.txt such as:

[HOST]
MyHostName
-plugin -connect MyHostName.dyndns.org:5500 -noregistry

Then the encryption WILL NOT work!!

However, if I specify an IP address instead of trying to use DNS or a DNS lookup service, then the encryption works perfectly, as advertised.

So, my recommendation to all of those trying to use the encryption with a dynamic dns hostname (such as dyndns.org) is to try it with the IP instead and see if it works.

It seems as though the DSM plugins does not like DNS names.

I have tested this thoroughly on my setup and this really does seem to be the issue. I don't know why this is not mentioned in any support or documentation. The whole idea of the UltraVNC SC seems pointless without ability to use encryption AND a dynamic IP/DNS name.

Perhaps the repeater option may work better with DNS names
archiboy
Posts: 2
Joined: 2007-06-09 09:33

Re: MSRC4 + SC Failure

Post by archiboy »

Update...

I was using the MSRC4Plugin.dsm version 1.21 (7/10/2006) which didn't seem to want to work with my DynDNS host name and only worked if I hard coded the IP address into the helpdesk.txt file.

So I went to http://msrc4plugin.home.comcast.net/msrc4plugin.html and downloaded version 1.22 - (8/16/2006) of the plugin (MSRC4Plugin122.zip).

I extracted the plugin and renamed it from MSRC4Plugin_NoReg.dsm to MSRC4Plugin.dsm and copied it to my C:\Program Files\UltraVNC directory. I deleted any other plugins that were in my \UltraVNC directory

(actually I did save a copy of the old plugins in the \UltraVNC\plugins directory just in case I needed to revert to old version for some reason).

I've read that renaming the plugin is not necessary, but I personally couldn't get it to work without renaming it.

I generated a new rc4.key file with the 1.22 version of the plugin. I renamed the key from new_rc4.key to rc4.key and put a copy in my C:\Program Files\UltraVNC directory (made sure to delete any old keys first). I then recreated my custom SC using a copy of the new key and a copy of the version 1.22 plugin.

I launched the viewer with the following options:

"C:\Program Files\UltraVNC\vncviewer.exe" -dsmplugin MSRC4Plugin.dsm -listen 5500

Low and behold THIS WORKED. I was able to use my dyndns host name and encryption and everything worked as advertised!

The HOST line in my helpdesk.txt file looks like this:

[HOST]
MyHostName
-plugin -connect MyHostName.dyndns.org:5500 -noregistry

where MyHostName is obviously substituted with the actual name of my host.

I think it is easy to get the combination of plugins and keys mixed up when trying to get this to work and testing all the different combinations.

You really need to delete all plugins and keys then copy the new version of the plugin to your UltraVNC directory and then generate a new key. This will prevent using the wrong plugin/key combination. It might be tedious but using patience and a careful methodology helped me to get it working.

Hope this may help someone!
Last edited by archiboy on 2007-06-09 12:58, edited 1 time in total.
beporter
Posts: 4
Joined: 2007-02-12 18:18

Re: MSRC4 + SC Failure

Post by beporter »

To sum up: it looks like the key to this process seems to be to include the RC4 plugin in the custom.zip that you upload to the server, in addition to using it on the viewing machine.
ChDante
Posts: 1
Joined: 2008-11-26 20:49

Re: MSRC4 + SC Failure

Post by ChDante »

After trying to get the encrypted version to work for a day, I finally managed to get a connection.

I do not think that DNS is a problem - works fine here.

I blame the issues on the MSCR4plugin and the shortcut.

This is how I got it to run:

0. Installed UltaVNC - viewer only, version 1.0.5
1. Create Helpdesk folder including all wanted files (background.bmp, helpdesk.txt, icon1, icon2, Logo.bmp)
2. Using the MSRC4Plugin-122.dsm (in C:\Program Files\UltraVNC)
3. Rename it to MSCR4Plugin.dsm
4. create new_rc4.key
5. rename to rc4.key
6. copy MSCR4Plugin.dsm and rc4.key to Helpdesk folder
7. create a zip-folder (Right mouse-click/Send To...)
8. create .exe file (via web page)
9. verify the shortcut in the start menu points to :
"C:\Program Files\UltraVNC\vncviewer.exe" -dsmplugin msrc4plugin.dsm -listen 5500
In other words: archiboy found the solution and pushed me in the right direction. If you look at the compiling process, you'll see that the plugin conversion uses the name "MSRC4Plugin", not "-122" or "_NoReg".
tsw
Posts: 5
Joined: 2009-02-18 09:20

Re: MSRC4 + SC Failure

Post by tsw »

archiboy wrote:Update...

I was using the MSRC4Plugin.dsm version 1.21 (7/10/2006) which didn't seem to want to work with my DynDNS host name and only worked if I hard coded the IP address into the helpdesk.txt file.

So I went to http://msrc4plugin.home.comcast.net/msrc4plugin.html and downloaded version 1.22 - (8/16/2006) of the plugin (MSRC4Plugin122.zip).

I extracted the plugin and renamed it from MSRC4Plugin_NoReg.dsm to MSRC4Plugin.dsm and copied it to my C:\Program Files\UltraVNC directory. I deleted any other plugins that were in my \UltraVNC directory

(actually I did save a copy of the old plugins in the \UltraVNC\plugins directory just in case I needed to revert to old version for some reason).

I've read that renaming the plugin is not necessary, but I personally couldn't get it to work without renaming it.

I generated a new rc4.key file with the 1.22 version of the plugin. I renamed the key from new_rc4.key to rc4.key and put a copy in my C:\Program Files\UltraVNC directory (made sure to delete any old keys first). I then recreated my custom SC using a copy of the new key and a copy of the version 1.22 plugin.

I launched the viewer with the following options:

"C:\Program Files\UltraVNC\vncviewer.exe" -dsmplugin MSRC4Plugin.dsm -listen 5500

Low and behold THIS WORKED. I was able to use my dyndns host name and encryption and everything worked as advertised!

The HOST line in my helpdesk.txt file looks like this:

[HOST]
MyHostName
-plugin -connect MyHostName.dyndns.org:5500 -noregistry

where MyHostName is obviously substituted with the actual name of my host.

I think it is easy to get the combination of plugins and keys mixed up when trying to get this to work and testing all the different combinations.

You really need to delete all plugins and keys then copy the new version of the plugin to your UltraVNC directory and then generate a new key. This will prevent using the wrong plugin/key combination. It might be tedious but using patience and a careful methodology helped me to get it working.

Hope this may help someone!
Archiboy!!!! you are a God-sent!
I thought I was losing my IQ till I found your post...

To all who has this problem, the answer is what Archiboy found... maybe, a bug in the documentation for SingleClick:

To use the latest codes, YOU HAVE TO INCLUDE the DSM in the custom.zip or xxx.zip of your customSC archive BEFORE uploading to the online SC creator tool!!!!!

THANK YOU, now it works!
dghundt
8
8
Posts: 14
Joined: 2009-04-11 21:01

Re: MSRC4 + SC Failure

Post by dghundt »

tsw wrote: To use the latest codes, YOU HAVE TO INCLUDE the DSM in the custom.zip or spam.zip of your customSC archive BEFORE uploading to the online SC creator tool!!!!!
Thank you to everyone before me. Beautiful posts.
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