Connectify Filter Driver Is Disabled

Connectify Hotspot relies on a filter driver, the Connectify LightWeight Filter, to share your internet connection with your devices. Sometimes this driver gets turned off on a network adapter, for example by antivirus software or by a Windows update.

When that happens, Connectify Hotspot can't start, and when you click Start hotspot it shows this error at the top of the window, titled Network adapter problem:

Could not start the hotspot because of a problem with this PC's network adapters: The Connectify LightWeight Filter driver is disabled on adapter. Go to Help and account > Network connections, click Open, and turn it on in adapter's Properties.

Instead of adapter, the error names the network connection to fix, as Windows shows it in Network Connections (for example "Ethernet" or "Wi-Fi"). It is the connection you chose as Internet to share, or, in Wired router mode, the Share over port.

How to turn the Connectify LightWeight Filter back on

1. In Connectify Hotspot, click Help and account.
2. Next to Network connections, click Open. This opens Windows' list of network adapters. (You can also press Windows+R, type ncpa.cpl and press Enter.)
3. Right-click the adapter the error names and choose Properties.
4. In the list of items the connection uses, make sure Connectify LightWeight Filter is checked, and click OK.
5. Go back to Connectify Hotspot and click Start hotspot again.

If the error names more than one adapter, repeat these steps for each of them.

If Connectify LightWeight Filter isn't in the list at all, the driver is missing. Reinstall Connectify Hotspot, which installs the driver again.