- Look up your computer here for drivers: Drivers and Downloads | Dell [United States]
- download the correct network drivers and save them to your computer
- uninstall your current wireless network adapter software
- install the recently downloaded one
- enter the correct information into the install wizard, and post back if this fixes anything
This is assuming the wireless adapter is indeed the problem.
To completely remove the previous wireless adapter software, use Revo uninstaller
. This way, it will remove all files and may increase the chances that this will fix the problem.