Can't Observe/Control

3238 is a typo. 3283 is the correct port.

That's what I thought too, except that on the Intel computers it says port 3238 in the yellow boxed text that pops up when you leave the cursor over the "Apple Remote Desktop" line under the Firewall tab of the Sharing pref's.

This "hint-like" yellow boxed text is input by Apple and not changeable by a user.

Check it out for yourself.

Same issue with inability to connect on upgraded 10.3.9 client now running ARD v3.1. Turned off firewall, turned on, added port 3283. Turned off again. Rebooted about 5x. After last reboot now it works. No rhyme or reason. Perhaps the Firewall settings sometimes do not stick?

If you haven't already completed your modem settings via a web browser do the following: Go to 'Port Forwarding' and forward the following ports 5900, 5988 and 3283 for traffic IN and OUT. Save and restart your modem. In System Preferences do the same in SHARING system preferences. If you send me email I can give you more assistance.

I had a similar problem on our network where I could see certain computers, install software and do other admin tasks, but couldn't get the computer's screen to open on the admin machine. I was able to fix this by going into the software firewall and enabling the VNC service, which opens 5900-5902 TCP and 5900 UDP. (obviously this will only work if you are using the software firewall)

Hope this helps someone. It was immensely frustrating to be able to do remote tasks and not be able to control the computer.

I was hoping this topic would help. My client is in another city and I connect via the Apple VPN. Machines that have been working will now not allow me to control/observe but everything else works. The built in firewall is off and hasn't been touched. I tried remotely reinstalling ARD, then turned that off and install Vine (VNC server) and got the user to configure it and still no go. Something is blocking it but as I said the firewall is off. Using ARD 2.2 but was going to consider upgrading but vine didn't work, might have to test when I go up there. It's now happened on 5 machines out of 50 and on all the new ones. I wonder if it was an update sometime...

There doesn't seem to be a recognizable pattern yet as to what is causing this problem.

Lots of users are having the same problem but Apple apparently doesn't read these Discussion Groups.

Or care enough to fix this problem

My problem: PPC G5 can control PowerBook G4, but the PB G4 cannot connect to PPC G5. The PB G4 could send a message but not control.

Having reviewed this thread I added the VNC rule to the firewall of the PPC G5 and the PB G4 was able to connect and control.

Both of the machines began with earlier versions of the OS and ARD installed, and have been updated regularly. The PPC G5 firewall rule for ARD says it opens port 3238 for UDP and TCP. I think this is a typo in the System Prefs software module; all the documentation I have read refers to 3283 only. The PB G4 ARD rule says it opens ports 3283 and 5900.

It appears that ARD v1 used port 3283. ARD v2 introduced the use of TCP ports 5900 and 5988.

Mac OS X (10.4.8)

I'll post my experience with this problem. Hopefully it might help some out there. I've posted a few times on this topic but have yet to get any help. Originally, I was trying to use ARD over Hamachi. When I ran into problems with this I took a step back and tried to get ARD to work over the local network first and found I couldn't control the one computer across the LAN either.

To resolve this (after trying many other options) I ended up removing ALL of ARD (as described in some other threads) including the client software then re-installing OSX, re-updating and re-installing ARD and it's updates. Four hours later, everything worked and as figured, once it worked on the LAN, it worked over Hamachi as well.

As long as you are sure it's not a firewall issue or a conflicting VNC issue, this may be your last resort. I believe the culprit would have been in the client software built into OSX as I also couldn't use any other VNC software to control the mac as well.

Hope this helps anyone else struggling with this problem.

Thanks for continuing interest in this thread, maybe if it gets long enough Apple will notice it.

Unfortunately I don't have access to the Intel MacMini's anymore so I can't try the re-install suggestion.

I did it, nothing else worked, but phew!!!
I removed system/library/coreservices/RemoteManagement

Installed it from the installer I made from within ARD. I had to run the upgrade as well. (not sure how this will go on an intel) and I can get back in now. Maybe if I grab a copy and set up an installer to fix this it might work, another day. I have 4 to fix. Thanks for all the suggestions.

I am awesome. This problem is definately an issue that is caused by the local computer's firewall. We can all now mark this one resolved!!!!! Go to a computer that you can control/observe and copy /Library/Preferences/com.apple.sharing.firewall.plist to the non-working machines /Library/Preferences folder , RESTART, and Yes, It now works!!!!!!

Or you can just take a second and edit the com.apple.sharing.firewall.plist file. I have a pic of my plist file but I don't think you can add those here.

In my earlier post I mentioned I was able to fix the problem by enabling VNC in the software firewall of the client computer. This worked on one machine, but had no effect on another. Both similar G5 towers. Still puzzled by this behavior. It seems so random...