Npcap 1.31 Setup "Failed to create the npcap service" error

Question

When I try to install Wireshark latest stable version (https://www.wireshark.org/#download) with all optional installs, I am getting "Failed to create the npcap service: 0x00000000. Please try installing Npcap again, or use the latest official Npcap installer from https://nmap.org/npcap/" error pop-up window during Npcap 1.31 installation. When I try to install the latest Npcap 1.50 from the site above, I am getting the same error. How can I install Npcap?Error window

Answer 1

Currently Npcap 1.50 is the latest release, so that's the version I'd recommend you try installing. But, if you're having problems installing that version, then you might want to read the Npcap release notes for version 1.50. Perhaps this bullet item applies to you?

Due to Microsoft's deprecation of cross-signed root certificates for kernel-mode code signing, Npcap 1.40 may not install correctly on Windows versions prior to Windows 10. Our testing did not show any issues, but users who experience installation failures may use the /prior_driver=yes installation option to install the Npcap 1.31 driver instead, which has no such issues.

Or maybe Npcap issue #517 - npcap 1.50 fails to start service on Windows 7 applies to you, in which case you might want to follow that issue. If none of the Npcap issues currently filed apply to your situation, then you should consider opening your own issue.