# How to copy and paste your serial number

A serial number typed by hand is easily mistyped. Copy it from your order confirmation e-mail instead:

1. In the e-mail, select the whole serial number and press **Ctrl+C** to copy it.
2. In the Register DU Meter window, click **Enter your serial number**.
3. Type the user name in **User name** *exactly* as the e-mail shows it, or copy it the same way.
4. Click in **Serial number** and press **Ctrl+V** to paste it.
5. Click **Register**.