Even if a keygen looks clean, it often modifies system files to "crack" the software. This triggers your antivirus for a reason—it is tampering with your PC.
: Your unique license key and registration details will be sent to your provided email address immediately. How to Activate Visual Subst Once you have your key, follow these steps: Visual Subst application. Click on the Enter License Key Visual Subst License Key
To summarize the situation: