I have an program that is supposed to run on all computers when a fire alarm is trigger and display a full screen message and play a .mp3 file. I can get the sound to play on computers were no one has logged in and it is still at the "press ctrl alt del to log in" screen but I can't get a full screen message to open up because there is no active session to open it in. Does anyone know if there is a way to get a message to display at the "press ctrl alt del to log in" screen before someone logs in to windows.
My current application is written in C# but I will rewrite it is another language if someone knows a way I can get this message to display, using another language.
All the computers will be windows 7 machines.
I have found the you can customise the login screen http://msdn.microsoft.com/en-gb/magazine/cc163489.aspx but that is still before the the ctrl alt del screen. I have also read that viruses can put a screen in before the computer loads the ctrl alt del screen but this seems to be booting to a different screen and I want it to be able to be display when it gets a message.
If I can't get a screen to display at the ctrl alt del screen, would it be possible to login and load a full screen message before the desktop loads?