You mentioned that since from the start, you were not able to utilize the Windows Store to download apps. For us to isolate further, we would like to verify if you are also having the same issue when logged in on a different user account. If you haven't tried it yet, we suggest that you create another user account, and then see if the issue still persists.
Knowing the result will help us determine if the issue is related to a user profile.
If the issue still persists on a different user account, we need to know more information that might be helpful in determining its cause:
- Is the issue persists on a different network, or when you are connected via different Internet service provider (ISP)?
- Are you connecting to the Internet using a proxy server?
- Other than Kaspersky, are you using any third-party firewall or security software?
- Did you configure your Internet connection to use a specific DNS server other than what the ISP provided?
- Have you tried performing a clean boot in Windows?
- Have you tried logging out, and then log back in to Windows Store?
- Is your computer's date and time, as well as timezone appropriate to your location?