If the wireless card came installed by factory, the computer manufacturer would be the first option for assistance. Here is the link: Drivers & Downloads | Dell US
For your convenience only, you can also take a look at this third-party website as it may help you find a solution for this issue: Driver Doctor
*NOTE: This link is being offered for your convenience and should not be viewed as an endorsement by Intel of the content, products, or services offered there.
Please, consider taking a look at your firewall and antivirus configurations as it may impact your connection.
If your wireless card is Intel's. Please take a look at the solutions available in the links below. If your computer manufacturer inform you that you also need our assistance, please make sure to inform what kind of adapter you have such as name and model so we can provide you proper support.