Dell e5450 scroll pad is not working

I suggest you click on start, control panel, mouse, click on the touchpad and check if the touchpad is enabled. The best thing to do would be to uninstall and reinstall the touchpad drivers. Click on start, right click on my computer, click on properties, click on device manager, click on the + symbol next to pointing devices, right click on Dell Touchpad and click on uninstall, click ok to confirm. Once its removed do not restart your computer, click on the below link to download and install the touchpad driver, and then restart your computer.