Recently, after prompt initiated update, the Wireshark could no longer detect my ethernet interfaces, leaving only USBs on the list.
Since problems persisted after reboot I decided to reinstall Wireshark with all the same options. The situation didn't improve, at which point begun to suspect the driver.
Quick check gave me conflicting information.
>sc query npcap
SERVICE_NAME: npcap
TYPE : 1 KERNEL_DRIVER
STATE : 1 STOPPED
WIN32_EXIT_CODE : 31 (0x1f)
SERVICE_EXIT_CODE : 0 (0x0)
CHECKPOINT : 0x0
WAIT_HINT : 0x0
>sc qc npf
SERVICE_NAME: npf
TYPE : 1 KERNEL_DRIVER
START_TYPE : 1 SYSTEM_START
ERROR_CONTROL : 1 NORMAL
BINARY_PATH_NAME : \SystemRoot\system32\DRIVERS\npf.sys
LOAD_ORDER_GROUP : NDIS
TAG : 28
DISPLAY_NAME : Npcap Packet Driver (NPF)
DEPENDENCIES :
SERVICE_START_NAME :
>sc start npcap
[SC] StartService FAILED 2:
The system cannot find the file specified.
>sc start npf
[SC] StartService FAILED 2:
The system cannot find the file specified.
So apprentlly, the service was present, but couldn't start, because relevant file was missing. With Wireshark still coming up empty, I decided to uninstall npcap also, and start with a clean slate.
Unfortunately, uninstalling Npcap turned out to be harder than I thought, failing and producing following log:
Reading service options from registry
Windows CurrentVersion: 10.0 (Win10)
Trying to stop the driver..
Stopping the npf driver
The Npcap Packet Driver (NPF) service is not started.
More help is available by typing NET HELPMSG 3521.
Stopping the npcap driver
The Npcap Packet Driver (NPCAP) service is not started.
More help is available by typing NET HELPMSG 3521.
Npcap service is not pending to stop.
Npcap. Device manager also detected the Npcap loopback interface.
So the driver service wasn't running but apparently some vestige of it remained. As a test, I tried to reinstall Wireshark, along with Npcap.
To my surprise, the Wireshark detected Npcap (of appropriate version) and didn't let me install it again.
And finally, I checked the:
C:\Windows\System32\drivers
To see if the relevant files are present, only to find both of them.
This is all the more vexing, because I have the same version running on my laptop. I don't know where to go from here.
Best Answer
The issue were old Npcap drivers in Windows driver store file repository. For reasons beyond my knowledge neither the installation or removal procedure detected them.
While I'm not completely sure how, these leftovers blocked installation of full Ncap driver suite. To remove them I used following batch script (from Jonatan Van Hove):
Afterwards I simply reinstalled Wireshark, to find it's functionality restored. So far I haven't encountered any further issues.