Are you having a problem with your modem? Normally you don't need to use a used modem as the Telus installers will give you one when setting up your service. They'll also give you a replacement if the first one develops problems that cannot be fixed by regular troubleshooting.
The modems are not registered to an individual account. They can be re-used as long as they match the line type. ADSL2+(slower/older) vs VDSL. If it's an Actiontec or a Zyxel (non-Optik) modem from Telus, you should be able to use them without issue, assuming you already have internet service from Telus. (Actiontec if you have Optik)
If you find a post useful, please give the author a "Like" or mark as an accepted solution if it solves your trouble. 🙂
