ARD 3.9: Authentication Failed

I have one site that this does not work on at all. Regardless of whether I connect with the original admin user or the newly created one, I get Access Denied. Can still observe and control but no remote management (unix commands/reboot etc).

I have experienced this issue as well. Inside the Window list with all of your clients. Select your client that has 3.9 installed.

- Right click, select "Get Info".

- Select "Edit" and enter your DNS info if necessary.

- Next, change the User Name to the corresponding short name. EX: "Admin Remote" to AdminRemote

Once I made this change, I immediately gained full access and control over my clients.

Hope this helps.

I can tell when I'm out of my depth. If "turn it off, turn it on" doesn't work, I've learned it doesn't help to wade in and start stirring up a bunch of setting. Like some of the others here, I'm responsible for dozens of Mac's and without ARD, we've got trouble. Still, it may be better to hold your breath and wait for Apple to fix this than chase all the hopeful fixes and other helpful guesses these fora offer.

Just saying, after years of dealing with this sort of thing, I've learned to separate Apple's problems from mine. ARD not working causes other problems for me and I'm dealing with them one USB drive, AirDrop, BlueTooth transfer, cloud copy, etc. at a time.

Here's how it should work: We tell them the problem, they give us the solution. In the meantime, it would be a kindness if they say they know there's a problem and they've got their best minds work hard on our behalf. Give us something to believe in.

Recent experience suggests that would be even more acceptable than the truth.

Well, thanks to everyone for suggestions, I have tried them all. Of the 5 machines I manage using ARD, 3 are now reachable, but I still have two who now show up without the access denied, but when I attempt to control or observe, I receive an "authentication failed" message even after toggling the check box in preferences for "Allow communication with older clients (less secure)" Its baffling given some of these are identical machines and OSX versions. Talked to an Enterprize support engineer and they are aware of the bug and are working on a fix, so stay tuned.

Hello. I can't connect to Windows XP through Apple Remote Desktop, but through Microsoft Remote Desktop connection is established. Please help.

Apple RD - Version 3.9

Microsoft RD - Version 8.0.38 (Build 27253)

Thanks

I have been experiencing this ARD Authentication Failed problem on some of my machines on the other end of a WAN link. It turns out there is a problem with the MTUs between the two endpoints of the WAN link (it was somehow set to 600). Setting the values to more normal and bigger values fixed this for me.

I hope Apple sees the urgency of this. Someone in the software dept made a big big screw up.

Creating a new Admin user account did not work for me. Everything running smoothly before.

macOS 10.12.3

I did this last night and it worked on 5 of 10 clients in one remote office. Helpful...

This worked for me. Apple needs to fix this.

This worked for me for a while and then they reverted back to not connecting - have yet to find an alternative fix. Have not tried the new admin user - would rather avoid that if possible.

Changing to short name worked for me... so far.

Worked for me on 2 of three machines. Thanks much!

Third is a no go.

There are several thread on this already (including one by me). In ARD, go into Preferences, select the Security tab and then check "Allow communication with older clients (less secure)."

Not the issue. Clients are updated.