Mac VNC not working after Security Update 2016-002

This may be useful - it works for me...

I have a mac mini which I access remotely for iOS development. I just "turn it off" with the button after I close VNC client - it goes to sleep actually.

Yesterday I got the same error after reconnecting. But curiously, after reboot I was able to log in.

As if something suddenly prevented me from logging in as the already-logged in user.

As a result I found out that if I log out of the user session prior to disconnecting, I am able to login the next time...

(but the real cause of this is unknown to me)

My Macbook Pro will not start up at all after this latest download. Is the machine trashed?

Help!

before this updates, the scenario here was:

- 1 iMac with Yosemite

- 1 person working directly on iMac

- 2 guys connecting to iMac from Windows using VNC

- The iMac must be logged for the others 2 connect on separate session.

- If the Mac was on users selection and someone connect on Mac with VNC, this user control all the Mac, and the screen will be mirrored for all, every user won't get a separate session. To get right, all users must be disconnected including the iMac, and then connect first on iMac and then the others can connect.

after the update "Remote Desktop client update" and "safari update" we couldn't connect to Mac anymore, the "securit update 2016-002" wasn't installed yet.

if the iMac is on the users selection screen, I'm be able to connect on Mac, but the screen will be mirrored, but we won't be able to connect on separate sessions anymore.

Now we are updating the Mac to El Capitan.

When the installation finish, we will test and get you noticed.

FINALLY!!!

It works again!!!!

We just updated to El Capitain and worked again!

🙂

Same problem here. Not 100% sure if it was the Security Update 2016-002 (10.10.5) or Remote Desktop Client Update v3.8.5 which installed the day before.

As other users had noted, if the mac was logged out then a VNC connection would work. If that user was logged in locally, then the error message would show with lots of errors in the Console logs.

Tried lots of workarounds with no luck, in the end had to upgrade from Yosemite to El Capitan - which worked.

I also had this problem after applying the latest security updates but I've since sort of resolved it without updating to El Capitan. The problem remains but can be avoided if your circumstance allows. Here's how:

1) Use Screen Sharing app (or ARD client) on another Mac and login. (This might also work from the local KVM)

2) Log off of remote Mac (don't just disconnect or close Screen Sharing without logging off)

3) Use VNC to connect to remote Mac.

4) Profit

Caveat: The remote Mac must be logged off if you want to connect with VNC. Simply disconnecting the session will make that error message return when you try to connect again. It seems that as long as the Mac is at its login screen and not logged in, VNC will connect after this update is applied.

I know this isn't a solution for everyone if they rely on the remote Mac being logged in all of the time, but it might help others who don't have this requirement. At least until Apple fixes it...

Confirmed: login still possible if remote is logged off

Just a FYI, issue is happening to Mavericks too. Came across this thread by searching on the error. Updating to El Cap works, BUT, ran into a different audio bug that happens with multiple browsers and on a clean install, so that didn't do the job. Reverted to the Mavs for now.

One thing I did notice is that whatever method it's using, the PocketCloud app on my ipad still logs fine into the system. Not using VNC?

Yes seeing this with Mavericks once I upgraded to 3.8.5 ARD. Looks like Apple broke ARD AGAIN. Tried the command line listed above, doesn't work for me on Mavericks, still get "The user account you selected isn't available".

Only way it works is being logged out, then one can log in. Not a good solution, since if the connection drops while you are logged in, you are no longer able to log into the account.

I have the same issue (10.10.5) but to complicate this, I CAN use Android app Jump successfully ALL DAY LONG. But it has two settings for VNC, 'password' and 'Automatic'. The connections that work specify a USERID and PW. So what seems to have broke is the validation passthrough to just use the PW, when a userid is not specified. This is all speculation, but I imagine the client is saying that the USERID is BLANK and that user cannot login because any account does not match.

Also, this broke only a SHORT time ago for me, and I have yet to apply Security Update 2016-002

softwareupdate -l

Software Update Tool

Copyright 2002-2012 Apple Inc.

Finding available software

Software Update found the following new or updated software:

* Security Update 2016-002-10.10.5

Security Update 2016-002 (10.10.5), 449922K [recommended] [restart]

* iTunesXPatch-12.3.3

iTunes (12.3.3), 118696K [recommended]

Makes sense to me, because PocketCloud uses a username/password combo too and it still worked. Actually, starting with my upgrade from 10.6 to 10.9, I noticed a difference in VNC log-ins. In Snow Leopard, I could log in and it would go straight to desktop. When I went to Mavericks, I would log in, and then have to log in again like I was logging into the mac itself, whereas PocketCloud would just go straight to the desktop still, and the only difference I could figure out was that PocketCloud was sending both a username and password when logging in.

Yes in the older versions it was direct. ML (iirc) introduced the passworded login screen, and that had been working, both on ML and Mavericks for me.

Using either TightVNC viewer or RealVNC on the control computer, the Mac would allow the login 1st with the VNC password, then display the secondary screen to re-login as the user with the user's password. And you could see the desktop and all the running apps.

No where I could find in TightVNC or RealVNC a username entry that seemed to pass to the remote computer.

DaveInSac, what version of 3.8 are you using? I am working out downgrading from 3.8.5 since it looks like Apple bodged it again. (did it in 3.7 too...) They must run a cut rate QA department for Remote Desktop Admin.

And (for me anyway) I didn't need to log all the way out - just go to the Login Window, which might only be available if you have fast user switching turned on. This way I didn't lose all of my active windows and context.