We have three terminal servers here (all Windows Server 2008 R2). Starting this past Monday, all 3 have (2 more so than the other) have been having this strange issue where some folks can login, and some folks connect to just a blue screen (no login prompt). After researching online, I found killing explorer.exe process tree and then re-starting explorer.exe fixes this issue. While that has worked, there are occasions where I have had to reboot the server entirely (as I've started task manager to kill explorer and it just hangs, nothing happens). This has been an almost daily occurrence.
Any idea what could be causing this to happen? Every article I've found shows it as a "one time" bug.