Trend Micro must be reinstalled every three weeks or won't update

Hi crousect and welcome to the community!

Have you tried doing this guide in order to make sure the problem gets resolved completely?

"Connect to the Internet" error message appears from Trend Micro Security software

Please read through the steps and perform then in the order shown so that the issue gets resolved.

Yes, I follow all the suggested solutions. The last step is to reinstall. After the reinstall it works normally again.

But after it works again, the update won't work again after three weeks? Is that correct?

If yes, can you try monitoring what happens within the duration of the three weeks where it works fine? If it keeps happening, then there should be some sort of pattern or program that could be corrupting the Trend Micro program to a point where it consistently malfunctions.

Also, the product should check for updates automatically every three hours. If you haven't used the computer in a span of three days, it will show you an error message similar to what you see. It is possible that this is why you get the error. Do you leave the computer unused for 3 days or more?