I am having the exact same problem. Screen sharing not working after updating. Remote server running lion server, my mac running mountain lion. Had no problems before updating. Worked once, then not before restarting the server - then worked once again and then no more. Since this is a web server I can not keep restarting it
This must be a bug from Apple. Would be nice to get a comment from Apple on this - seems like ther is a lot of people struggling with this.
The MobileMe solution would perhaps be ok, if I had mobileme in my prefs pane (which I dont!)
I also have some problems with TeamViewer after upgrading to mountain lion. TeamViewer simply doesn´t start!
Turning Screen Sharing on/off is not an option for me as I using "Remote management"... Come on Apple... Fix this.mwakefield wrote:
I am having the exact same issue/temp fix scenario. This is very annoying.
I'm thinking of to a wiping the hard drive and putting on a fresh copy of Lion to see if that fixes the issue.
Actually, I did that and have a fresh install of 10.8. Still have the same issue.
If I reboot screen sharing works fine for about 15 minutes.
I'm using a Mac Mini as a headless media server. So I have to use screensharing to connect and manage the box. I have also tried Apple Remote Desktop and I have the same issues with that as well.
I have been noticing some weird power management related issues with 10.8
I have had to change my energy saver preferences from the defaults when reading and wiriting to a DVD on my ol 2007 MB Pro running 10.8. I would get timeouts and unable to read the disk errors after 15 straight minutes of SuperDrive access and I'm not doing any mouse or keyboard input. The screen goes blank and then I notice that the drive stops being accessed. I then notice that the app reading the the SuperDrive reports errors accessing the disk in the drive. I haven't even tried burning a DVD since this has been occuring because I don't want any toasters.
Anyway, here is what I am going to do. I am going to modify my energy saver preferences on the Mac Mini to not go to sleep and see if that effects screensharing. I'll report back.
BTW, I have tried all the troubleshooting tips on this thread and I am still having the same issues.
Try restarting the server Mac (and make sure you do the software update that affects screen sharing). Then try accessing it only through Apple Remote Desktop and not Screen Sharing. I found that I can access my server unlimited times if only access through ARD, but once I access with screen sharing, it starts the 15 minute clock and reboot required for either ARD or screen sharing. I believe the problem is with the login. Screen sharing launches a dialog box which is hidden on the client mac until the server restarts. I posted a picture of it earlier in the thread.
Not sure if I am have the same issue but it related and I am bring a post over, see Setup and Problem below. After fighting with my router for days, I have decided it is a Mountain Lion Issue. I am only trying to Screen Share with Back to My Mac. File sharing works great in all cases. I am testing with 4 macs:
MBP Mountain Lion (MBPML) - home network
iMac 1 Mountain Lion (iMac1ML) - home network
iMac 2 Mountain Lion (iMac2ML) - office network
iMac 3 Lion (iMac3L) - home network
1. If I try to screen share form MBPML or iMac2ML to iMac1ML with iMac1ML screen awake, Screen sharing works as it should.
2. If I try to screen share form MBPML or iMac2ML to iMac1ML with iMac1ML screen sleeping, Screen sharing will never start on the MBPML. The screen on the iMac1ML lights up but requires a reboot before screen sharing will work again.
3. If I try to screen share for iMac3L it works with the screen sleeping or awake as if the iMac1ML scheen sharing has not been lock up by trying to screen share with mountain Lion.
Over the past week I have changed every possible combining of settings in sharing and energy preference I can think of and still no joy.
Office iMac Mountain Lion Web static public IP
Home iMac Mountain Lion - ADLS modem/router/wireless Sagem Fast 1704 - wireless off - Time Machine Bridged to 1704 by either net cable - supports UPnP - NAT-DHCP IP number rant 192.168.254.1 - 192.168.254.254 - Internal router IP number 192.168.254.254
Wife iMac Lion connect wireless just like Home iMac
MBP - Mountain Lion connected to home network described above.
MBP is in the same room with Home iMac and Wife iMac.
From MBP I can screen share using Back to My Mac (BtMM) or a VNC client or the built in OX X VNC with no problems.
I can BtMM screen share to the wife iMac because it on the same network, it not on the same iCloud account.
The Home iMac screen shares works as expected if the computer is awake but if you try to screen share with the computer sleeing, the Home iMac computer screen lights up but the screen sharing never occures on the MBP. If you try to screen share with the Home iMac sleeping the only way to get screen sharing working again is to restart the home imac. As long as I wake the Home iMac before I screen share, it works fine. File sharing continues working. I have tried disconnecting file sharing, reconnecting file sharing, turning wake on network activity off. I have tried turning VNC connect off, just about ever combination of preference I can find and the only way to get screen sharing working again it restarting the Home iMac.
I can not reset the PRAM on the home iMac. With the computer off starting the computer and pressing option - command - p & r at the same time before the gray screen takes me to the recovery mode. I tried to reseting SMC. Can anyone give me a suggestion of how to screen share my Home iMac without turning screen sleep off. Most of the tries have been with computer never sleeping and putting hard drive to sleep when possible.
Mac OS X (10.7)
For anybody still having trouble, I found that a least for me, restarting the host computer made screen sharing work again. I have now narrowed this down further. If you go to Activity Monitor on the host computer, look for the process screen sharing agent. I have found that it has remained open when clients cannot share the screen with the host. Force quit that process and screen sharing now restored. No need to restart host.
Perry, You are correct, I think you found the bug. When I forced quit screen sharing agent, screen sharing started on the connecting MBP. Lion will connect to the mountain lion couputer when it is sleeping without a problem but mountain lion will not. Does Apple not know there is an issue? Is this not happening to everyone? Thanks for the discovery. Unless I am missing something, everytime a user tries to screen share Mountain Lion to a sleeping Mountain Lion computer, screen sharing agent hangs. No screen sharing will occure until a restart of force quit stops screen sharing agent. The computer with the screen sharing agent will not sleep either.