This could be caused by diverse issues.

1. Make sure you downloaded the latest version of the software
https://www.pulsar.gg/pages/download
2. Make sure that you are using a compatible computer: currently only Windows 7 and above are supported.
3. Close all other running mice or keyboard programs.

If this is still not working, please contact support and provide a video of the following steps:

1. Uninstall the software/Remove all installation files from your computer 
2. Go to our software download page
3. Download the software
4. Install the software
5. Open Task Manager (CTRL ALT DEL)
6. Close all running programs
7. Open the software