"Connection failed to ..."

If I recall correctly, try removing:
/Library/Application Support/Apple/Remote Desktop/Task Server/Settings.plist

and re-launching the Remote Desktop application.

You will have to do this as root from the terminal.

Some thoughts:

- if you haven't already, try removing the computer from the computer list in ARD and re-adding;

- if that doesn't help, or it can't re-add the system, confirm that nothing's changed in any necessary routing;

- Remove the ARD client on the problem workstation using the instructions here and then reinstall the client (this is, I'm sure, what Brian meant).

Hope this helps.

Wierd... what happend to the path...

/Library/Application Support/Apple/Remote Desktop/Task Server/Settings.plist

Is the problem client on a different network/subnet than the other systems?

I am having what looks to be the same problem. (10.4.9 on both machines, ARD 3.1 admin and client.) My problem machine connected fine for a long while, as well. I thought I was successful in solving it by logging out as one user on the problem machine, deleting client from ARD admin list, logging in as another user on problem machine, being able to connect to that user from ARD admin, deleting that 'successful user' computer from list, then logging out of that 'successful' user, logging back in as the original unsuccessful user, and was then able to connect - for about a week. Now I'm getting can't connect messages again, and repeating the above processes hasn't helped this time.

I have disabled ARD client using system prefs w/ no luck, as well.

Both client and admin are on same subnet.

I would also REALLY appreciate some help w/ this.

Forgot to mention that ARD admin 'sees' the correct user and app on the uncooperative machine now, so it is 'connecting' from that standpoint. When I switched users as mentioned earlier, the admin machine still showed the 'old user' as the active user, and it showed the correct app of the 'inactive' user as tho that was the active user.

That sounded like a good idea, and I tried it, but it didn't resolve the problem. Just to make sure we're talking about the same thing...

My desktop machine is the problem machine. I am usually running ARD admin on it, but when I am out of town, I Timbuktu into our server, which also runs ARD admin, and then access my machine from the server. I make sure ARD admin isn't running on my machine. For months it worked fine, but for the last 2 or so, I've been having problems as stated in earlier posts. I'm not aware of any changes in settings, etc.

I have been able to add my computer to the list on the server, it sees what app is running, what ARD client is installed, etc., but when I try to connect, I get the "connection failed to" message.

Did you do anything else when you deleted and reinstalled ARD? I followed the instruction in the ARD manual, and even restarted machine after deleting.

Needless to say, I'm very puzzled. It seems like the problem area is pretty narrowed down if the admin machine can 'see' my machine, as well as what app is active, but refuses - or is refused - a connection.

The other strange behavior I'm seeing is that when I hit the tab key, and I'm controlling another computer I get the result of command-tab on my machine, and my other keys don't work correctly until I close the computer's window in ARD and reopen it. As long as I don't hit the tab key, other keys work okay in ARD when remotely controlling a computer. Don't know whether this is related or not, but it is bizarre.

I too am having this issue. It seems to be a permissions issue on the client machine. We have the client machine set up to authenticate, when on the network, to our active directory server. I believe this is causing the issue, but am not finding a solution. Have you found a resolution for this issue?