Prevent ScreenSaver coming up with a PowerShell script

In our daily business, we often have the issue that a GPO enforces a screensaver after a certain amount of time. This can become very annoying and actually even be an issue if you are remote in on a end-user system and don’t know their password. After doing quite some research I found out that PowerShell actually is able to help here and I wrote a script to prevent the screensaver from coming up.

First I thought, let’s see if I can control the mouse cursor, cause I thought it would be less invasive, this is actually possible – but interestingly did not have the expected effect and the screensaver kept coming up. So I did go with keystrokes, but of course I was worried about what key would be save to send. Doing some research on Microsoft websites (here the link), I found the F16 – testing around with it I found it the least invasive key to send periodically to a system – it does not even exist on a regular keyboard and can only be simulated with a key-combination. To simulate F16 you need to press SHIFT + F4 – there might be a Windows 10 (may be even earlier) combination out of WINDOWS + SHIFT + F4 respective WINDOWS + F16 what would cause a shutdown. Once I found out about that, I decided to adjust the script to F17 what seemed to bypass even that small chance of an issue that would be more problematic then the screensaver itself – you sure don’t want the system to shutdown :-).

The script you find below can be simply executed. It has a setting $minutes that you could add as a parameter and therefor adjust it when you start it – by default it will use 9999 what is a pretty long time. To be clear – this is actually not a minute interval, it is a 30 second interval and ends up in half minutes. Why? Simple – Windows has a minimum setting of 1 minute that an screensaver can come up. If the script would fire in a minute interval, there is a theoretical chance the screensaver would still win.

This is further not pure PowerShell code – well it is but actually the key stroke is send via a Windows Scripting Host WSH / WScript command SendKeys. The PowerShell only surrounds to command. It has the nice habit of having a PowerShell window open that you simply can close to end the script. If you would do the same in WSH you would need to execute the script more manual with CSCRIPT rather then just double-clicking the file what would execute it via VBSCRIPT instead causing a hidden window / process and you would need to identify it in the task-manager to kill the process. Therefor, PowerShell was the best choice in the end to accomplish the task.