Upgrading 13.04 to 13.10

Upgrading 13.04 to 13.10

I'm trying to upgrade from 13.04 to 13.10.
I tried the following command in Terminal
sudo update-manager -d
The result showed:

I clicked on Upgrade
The terminal window then showed the following:
Checking for a new Ubuntu release
Real-time signal 0
Then nothing happens.
If anyone has any suggestions on how to proceed, I would be most grateful.