Can you change it in Windows?
If you have W10
1. Click window on lefthand bottom of screen
2. Click the 'cog' in the lefthand column for settings
3. Click Ease of Access
4. Click Mouse and change the pointer size and colour
If have any PC problems, anything to do with computers, hard drives, modems, wi fi, software, anything.
Try http://www.protonic.com free technical support run by volunteer technicians.