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Hi, Newbie! Having real problems with port fowarding :(

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Ryanrs
Posts: 5
Joined: 2010-07-04 10:07
Location: medway

Hi, Newbie! Having real problems with port fowarding :(

Post by Ryanrs »

Hi all. I am using VNC on my [SPAM] N900, i have got it working fine if i connect my pc direct into the modem but when i use it through the wireless router i cannot get it to connect.

I have configured the port forwarding for ports 5800 ~ 5800 and 5900~5900, and i try to connect with VNC on my phone , it thinks about it for about 10 seconds then tells me that it cannot connect to server. If i disable the port forwarding then it throws back a 'cannot connect to server' message almost instantly. This tells me that the port forwarding may be right but something is blocking it?

My wireless router is a D-Link DIR-615 and i have my pc hard wired into one of the 4 Ethernet ports (as i have no wireless card -but have 2 laptops that do).

My PC wireless IP is 192.168.0.100 and my address as displayed by the VNC server on my pc taskbar icon is 92.236.**6.66 However the IP address shown on my D-link router config page is 92.236.**7.29

heres my port forwarding screen.

Image

Can anyone help?
Thanks.
B
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Joined: 2009-09-09 14:05

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by B »

First, UltraVNC has a serious deficiency in that it NEVER checks for IP address changes after it's started. So if you're swapping things behind the scenes (e.g., moving from direct-modem connection to router/switch connection) your UltraVNC server doesn't know it. That would explain why the icon shows it still listening on a public address (and NOT on the private address).

I assume by "my PC wireless IP is 192.168.0.100" you mean the address handed to it the PC by the hard-wired router/switch connection, right? That is, you only have one local address?

I'm pretty sure if you just restart the VNC server / service whenever you change the network, you'll be on your way.

Also, personally, I'd pick alternate ports. The defaults are very frequently scanned by scumware.
Ryanrs
Posts: 5
Joined: 2010-07-04 10:07
Location: medway

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by Ryanrs »

You assume correct as to the what i mean by the Wireless IP.. it is hard wired into Ethernet port no1 on the back of the wireless and the ip is assigned as 192.168.0.100

I have restarted the VNC service and it is now showing 192.168.0.100 however i am still unable to connect. I have tried different port numbers and tried playing with the routers firewall settings but it makes no difference. I just get a 10 second pause then get told "cannot connect to server"

Any ideas?

Perhaps im doing something wrong thats a simple fix? would a prtScn of my server admin properties be any help? thanks.
B
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Joined: 2009-09-09 14:05

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by B »

When everything was working your PC held that other public IP address, right?

What IP address was held by your phone at the time? What address does it hold now? Is it still another public IP address (from your cellular carrier) or does it also have WiFi attached to your home network?

Sure, the more screenshots the merrier...
Ryanrs
Posts: 5
Joined: 2010-07-04 10:07
Location: medway

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by Ryanrs »

Ok well i have had another play about with the settings and finally i got it to work!! God knows how. I re-tried the ports config with no avail, then i released and renewed the DCHP and magically it worked! If my phone is connected to wifi then i have to connect to the 192.168.0.100 address and if im accessing through 3G then i use the main IP.

However!!!

I logged out to the XP login screen remotely and successfully logged back in but then all of a sudden its decided not to connect again :S I have the "Query on incoming connection" active and when i try to connect ,WIFI or 3G, the 'Accept confirmation' box appears but upon clicking accept, my remote terminal gets the 'Could not connect to server' error...

Any ideas?
Last edited by Ryanrs on 2010-07-06 21:26, edited 1 time in total.
B
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Posts: 2338
Joined: 2009-09-09 14:05

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by B »

Maybe out of synch with the prompt/accept/establish connection sequence; parts are timing out. (Just my guess.)

I would probably skip the query prompt option; it kind of defeats the purpose if you have to race back to the PC to accept each query; if you're going to be at the console anyway, you might as well start the VNC service manually only when needed, rather than leaving it up all the time.

Anyway, good to hear it's working.
Ryanrs
Posts: 5
Joined: 2010-07-04 10:07
Location: medway

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by Ryanrs »

Well i turned that on and set it to 'Accept' as then if someone tryes to connect to me, i will know.

Anyways, a little more progress made :

"Require MS logon (user/pass./Domain)"

I had this checked so i can log on remotely. I have now discovered that if i uncheck / disable this option, The remote terminal works perfectly and i dont get 'unable to connect' errors thrown up after accepting. But this means i cannot log in to XP remotely. I dont understand as it was working fine an hour and half ago :S
YY
200
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Posts: 996
Joined: 2006-11-13 15:11

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by YY »

Ryanrs wrote:I have now discovered that if i uncheck / disable this option, The remote terminal works perfectly and i dont get 'unable to connect' errors thrown up after accepting. But this means i cannot log in to XP remotely. I dont understand as it was working fine an hour and half ago :S
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 1.0.8.0, and I suppose 1.0.8.2 having the same issue, tested on WinXP system.


So try to input something into one of the three Group, to see if you can have the problem solved.
B
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Joined: 2009-09-09 14:05

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by B »

If UltraVNC is installed as a service, you don't need the MS Logon settings. Just leave the station logged out, and when you connect via VNC you'll have to log in to Windows normally using your usual Windows/domain login.

Good catch on the old bug, YY!
YY
200
200
Posts: 996
Joined: 2006-11-13 15:11

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by YY »

Hi! B,

I notice you have a very good job done --- gathering all known serious issues of UVNC into a single thread [topic=18351][BUG] Some Serious Bugs[/topic].

If possible, I appreciate you can record this problem into the thread too. Although not a really serious bug (at least there is a very simple solution to overcome it), yet sometimes it is very confuse as very little document mentioned on it.

I had posted this issue before (may be 2 or 3 years ago) for several times, but unfortunately the developer was too busy to spare a moment to fix this problem, and those threads were all erased when the site admin taking the clearance action of the old posts. I almost forget this issue as well. :|
Last edited by YY on 2010-07-07 15:30, edited 2 times in total.
B
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Joined: 2009-09-09 14:05

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by B »

Of course! I'd be flattered to do so.
Ryanrs
Posts: 5
Joined: 2010-07-04 10:07
Location: medway

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by Ryanrs »

Cheers for your help B. I tinkered with them settings and at first it wasn't giving me any joy.. Seemed that everytime i applied the settings, the VNC viewer would successfully connect once or twice but then after that i would get no joy until i 'Tinkered' and applied the settings again :s Bug perhaps?

But then magically its started working fine! 'touch wood!!' What i would like to do now tho is change the ports. Do you know what the port range is? or how i could find out what ports are free to use?

thanks.
B
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Posts: 2338
Joined: 2009-09-09 14:05

Re: Hi, Newbie! Having real problems with port fowarding :(

Post by B »

There are over 65,000 ports on your PC. Just pick two! Seriously, just about any of them will work.

I like to pick ones over 50,000, for no particular reason. The fact is that if you just stay away from 5800/5900 you'll be far less likely to get scanned.

See also http://en.wikipedia.org/wiki/List_of_TC ... rt_numbers

That list includes both "well known" ports and "registered ports" for common applications, including VNC.
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