Try turn off all firewall/antivirus, that might explain why you cannot connect to the activation server.
i just want to know why it did that when i did nothing to my hardware.
If you haven't changed anything in your hardware, a reactivation is not needed. But if you reinstalled Windows, then yes, it's normal.
Just installing a new sim doesn't do anything for the activation.
No informations related to it are ever stored in any of the files/locations that are related to the sim. We store your activation in our own section in the Windows registry so, as long as you don't reinstall Windows, they are entirely unrelated to the various sim you install or remove.
