Normally this problem is related to computer security.
Please check you are your antivirus. Is it updated recently? Because all anti virus only will give you complete protection if it is updated regularly. The default for this update is one week, after one week if still not update it will give you that security problem in the taskbar.
If you are using offline computer or very rarely online to the internet you can check the setting on the antivirus you are using. Please check in the update menu and check on teh option.

Thanks, I hope it will helpful for you.