Please try to activate Render[in] on your PC after ensuring the following:

1: You should have administrator rights to activate the product.
2: Disable temporary the firewall on your computer
3  Disable temporary the antivirus on your computer
4: Disable temporary UAC on your Windows 7 or on your Vista. After turning UAC off, please make sure that you restarted your computer.

For more info on disabling UAC on your computer, please read:

5: Try to activate Render[in]