my computer is not visible in my account

I have 5 systems in my avast account. 3 are PCs, 1 laptop and 1 mobile. Out of the PCs one of PC does not show in my avast account when I log from a browser to my.avast.com. When I go to this PC itself and try to login from the avast interface, it shows me an error “We cannot connect your device to the Avast account. Please try after some time”. This error message has been repeating for couple of months now. Kindly help. I am using Avast Internet Security 2015.
Thanks
Ashok Rao

Repair Avast:

  1. Control Panel → Add/Remove programs → Avast
  2. Click on ‘Repair’.
  3. Follow instructions.
  4. Reboot.