# Data limit alert

DU Meter can warn you before you run out of data. It watches your traffic today, this week or this month, and
warns you when it goes over a limit, or when the pace so far will take it over before the period ends.

Turn on **Alert me**, then choose one:

- **When traffic goes over a limit**: pick received, sent, or both, then the period and the limit. Weeks and
  months begin on the days set on the [History](https://www.hageltech.com/support/kb/du/using/options/database) page.
- **When the cost this billing period goes over** an amount. This needs a billing period, which you set up on the
  [Costs](https://www.hageltech.com/support/kb/du/using/options/costs) page.

Say your plan gives you 100 GB a month. If you have used 83 GB by the 23rd, you are on course for 108 GB, so
DU Meter warns you that day, five days before the 100 GB runs out.

### When the alert goes off

Tick everything you want DU Meter to do:

- **Show a message**: a window with the traffic so far.
- **Send an e-mail** to the address on the [E-mail](https://www.hageltech.com/support/kb/du/using/options/email) page. This is greyed until that page
  has an address and a mail server.
- **Disconnect VPN and dial-up connections**, **Block all network connections** and **Shut down the computer**
  wait 30 seconds first, in a window where you can click **Abort** to stop them.

Blocked connections stay blocked until the period is over, even if you restart the computer. To get back online
sooner, click **Stop connections blocking** in the alert window.