If you are having difficulty connecting to a wireless network, there are 3 main steps any experienced tech would do before advanced troubleshooting.

These steps are -

1. Check that the wireless adapter on the machine is switched on.
2. Ensure that you are typing in the correct password for that network.
3. Confirm that the wireless network is broadcasting.

If you are using a laptop, it is very common to find that the wireless adapter can be turned on and off with a switch.

With Dell machines, it is usually mapped to a function key (Fn). This involves holding down Fn on your keyboard and then pressing one of the F keys eg. Fn + F8. Other machines have a switch or button dedicated to this action. Have a look for the wireless symbols -

If you are using a desktop, check that the USB Wifi adapter is securely plugged in. Or if you have an internal wireless network card check that the antenna is screwed in correctly.

Always be careful when typing in the password for the network. Remember that this is case sensitive, so a "M" will be a different character to a "m". Be sure not to mix up the number 0 and the letter O and so on...

Always try a different device connected to the network to verify that it is active