If you can use something, it's useful. Useful things are handy for whatever you're doing. If something is just what you need or you just find it helpful, then it's useful. A hammer is useful in building many things. Coasters are useful if you don't want a coffee table to get stains. College degrees are useful â or necessary â for many careers.
Where is the security key on a comcast modem located? The security key on a Comcast Modem is located next to the serial  number of the unit. Sometimes the serial number is the number used  as a security code if it is not printeâ¦d on the device. (MORE) 1 person found this useful.
1 Log into your Comcast Internet service through the website. 2  Enter your username (email address) and password. 3  Select the Voice tab on the top of the Comcast menu. 4  You will need to log on again with your home telephone number as well as the password attached to the phone number. Press the # key on the phone. 2  This will pause your current message and you will be prompted to enter your password. 3  Enter the password using the keys on the phone and you will have access to checking your Comcast voicemail.