#NPCAP LOOPBACK ADAPTER INSTALL#
#NPCAP LOOPBACK ADAPTER DRIVER#
#NPCAP LOOPBACK ADAPTER SOFTWARE#

#NPCAP LOOPBACK ADAPTER SOFTWARE#

Software using Npcap should get this value automatically and no special handling is needed. Happy to help with further diagnostics / tests. The MTU of Npcap Loopback Adapter is hard-coded to 65536 by Npcap. I'm guessing Avast is denying npcap access to a network resource it requires, and that this is being reported as a generic file access error by the service manager.

De-install Avast, reboot computer, npcap now functions again.Дisabling all shields while Avast is installed does have any impact on the problem.

No interfaces are available in Wireshark as the packet capture service is not running.

#NPCAP LOOPBACK ADAPTER DRIVER#

Event log captures error event 7000 'The Npcap Packet Driver (NPCAP) service failed to start due to the following error: The system cannot find the file specified.' This error is reported with each attempt to start service via net start. Otherwise, you 'see' nothing else on the wire. Npcap continues to function correctly as before. Normally, the network interface only passes packets up the protocol stack if they meet certain criteria - most importantly, being addressed to your home address ranges (MAC, IPv4 and IPv6 IP addresses, sockets for active TCP and UDP connections, and so forth). Wireshark is able to capture packets via the service. Service can be successfully stopped and restarted via net stop / net start commands.

#NPCAP LOOPBACK ADAPTER INSTALL#

After install completes, npcap service is running - can confirm via powershell get-service.

On a machine without Avast installed, install npcap from - I have been using current version v0.993.

Other normal loopback adapters are not infected by NPcap.

What is an Npcap loopback adapter Loopback Packet Capture and Injection: Npcap is able to sniff loopback packets (transmissions between services on the same machine) by using the Windows Filtering Platform (WFP). Correspondingly, NPcap will add an adapter named 'NPcap Loopback Adapter', it is created just like a normal Windows loopback adapter, but NPcap will specially take care of it and make it see and only see 'real' loopback packets (like ping 127.0.0.0/8 or any local IPs). You must be connected to a network to see the loopback address. You can change the bind order for the adapters without reinstalling the loopback adapter. After the loopback adapter is installed, there are at least two network adapters on your computer: your own network adapter and the loopback adapter. Also found references to issue elsewhere, as yet unresolved (other than 'remove Avast') - and (German) The loopback address will appear on the Ping.exe screen that appears. When you install a loopback adapter, the loopback adapter assigns a local IP address for your computer. 535 Lenovo X61 / Win / Avast Internet Secuirty. Checked behavior on 2 different PCs - Lenovo X1 / Win / Avast Premium Security build. Avast is preventing me from running the packet capture service that is needed for Wireshark on Windows 10.