On a remote session on a domain server, at the login screen you get a message when trying to inject ctrl+alt+delete saying that you cannot because of the group policy of that domain.
Sometimes you pin a remote to work on later, after an office is closed, so that you can work on things without disrupting the work day. But what what do you do if you realize only later that you are on the login screen, and it is requiring you to hit ctrl+alt+delete to then log in, but when you try to inject it remotely you get an error message saying that the group policy does not allow it. Instead of waiting until the next day that someone is around to unlock this screen you may be able to open this remotely.
Note: This solution is for a fairly specific case. I accomplished this with a 2008 R2 server that had been pinned with Bomgar. It may be adaptable to other remote software, and other OS versions, but it will work at least with this combination.
Bomgar allows you to go to a different tab from the screen sharing to a command shell tab. This allows you to go there and put in the following command into a command prompt, which should then allow you to get to the password entry without ctrl+alt+delete. Just copy and paste this in there:
reg add “HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionPoliciesSystem” /v DisableCAD /t REG_DWORD /d 1 /f_
Once you do that, you can reboot the machine (the source below gives as command for that, but I just reboot it within Bomgar) and then you can get logged in and get to work. There are other ways to do this by actually getting into the group policy, so if you have access to the machine and notice the issue ahead of time, you can do it by editing the group policy, which would be another guide, which at some point I will get to, and hopefully remember to add a link here pointing to it.
If there is anything you think needs to be added, expanded upon, or corrected, you can comment below, or better yet, make some edits on this topic’s wiki page HERE.