Internet data being used/stolen

If anyone can help,

I use a IMAC with mac os 10.7 – I have 2 sources of internet – Wifi and a 3g card. Someone has been using my internet from both sources pending with one I am using at that moment. On my 3g card I can see the usage climbing even when all my programs including firefox and email app is closed. My firewall is on and my automatic updates has been switched off.

Please help – I don't know how to stop this.

Thank
Lea

Just turning off Firefox and your E-mail app isn't sufficient to limit Internet access, most modern OS' use the Internet has an always connected (and available) technology. There are many services/applications that run in the background that eat up bandwidth (usually a little though, not HUGE amounts)..

On your WiFi, what sort of security are you using? On your 3G connection, do you have to use a dongle connected to the iMac and the how do you authenticate?

It's very unlikely that someone else is using it as Raz0rEdge says. I'm assuming that your wifi is metered, as is your 3G. In this case, when you don't need it unplug the 3G dongle and turn off wifi from the icon on the menu bar

Thanks for you quick response.

I know it is suppose to use a small amount of data – but is uses 20mb in 10 min if all programs are closed. My 3g card is a USB Stick.

Thanks
Lea

I have a password on both!

Lea1977 said:

I have a password on both!

Click to expand...

On your WiFi you are using WPA/WPA2? and on your 3G, it's a strong password? Change both of them and then monitor the usage, if it continues to go up, it's you and your apps..

If that is case, we can dig further to see what's using the network..

As I had said earlier, more and more apps/services/OS' are using the Internet freely to enhance your experience and having capped Internet access will continue to become a huge annoyance..

also, maybe while you're checking, require that all need a password to sign in and don't put a check where it says remember my password...

Thanks will try changing the passwords and let you know!