Policy Banner issue with thunderbolt displays

[sardesm]

We are having an issue where the Policy Banner does not display at login. This usually happens with Laptops with a thunderbolt display but i have seen seen it on dual thunderbolt display machines. At login the user is presented with dual black screens,If you disconnect the TB display the Policy banner appears and a the user is able to login. Likewise if I remote into a machine i will see the policy banner and be able to click through to get the login.

Any Ideas?

[bvrooman]

I submitted this issue to Apple as bug # 19327689, and it was almost-immediately closed as a duplicate of 18525321. Unfortunately the latter bug is still open, and is not listed on Open Radar.

[charles_hitch]

This is a known issue when an external monitor is set as the primary monitor. If you leave the primary monitor set as the laptop screen you shouldn't have this issue. Apple is aware of the problem and they are working it.

[jrserapio]

Which OS are you running? We ran into it in Mavericks, but I believe was resolved in Yosemite iirc.

[sardesm]

Mavericks and Yosemite.

[jleomcdo]

We have the same issue with Mavericks and Yosemite. I found that if you remove the "com.apple.windowserver.plist" file from /Library/Preferences directory that will "reset" the display startup options. I created a policy that runs a the follow command and stuck it in Self Service.

rm -f /Library/Preferences/com.apple.windowserver.plist

Hope this helps!

[sardesm]

If the user cannot login this does not help obviously. I assume this would require some education, i.e. letting the user know to unplug the secondary display and then have them run the self service script after login.

[jleomcdo]

You are correct. Once they know to unplug the monitor and then to check Self Service. Most of our Mac users are in one department, so the word got around quickly.