How to Fix Wlanapi.dll

1. Download the Wireless LAN API update from Microsoft's website. It is also called KB918997.
2. Identify the manufacturer of your wireless card. This may be a third party or the same as the manufacturer of your computer. After doing so, search their website for an updated wireless driver and download it. This restores your wlanapi.dll file if it has been overwritten by another file.
3. Uninstall your current wireless card by clicking on the 'Start' button, then opening the 'Control Panel' and selecting 'Device Manager.' You will then see your current wireless card and can uninstall it.
4. Install the new driver by double-clicking on it.
5. Run antivirus software and a registry cleaner program to erase any lingering malware on your machine that might be interfering with the wlanapi.dll file.