Can't Delete ARP Cache on Windows 7 x64

When I enter the command line arp -d * at an instance of cmd.exe, I get

The ARP entry deletion failed: The parameter is incorrect

I can delete individual entries fine, e.g. arp -d 192.168.1.1

I also have Cygwin and Git Bash installed, so I thought maybe the * was getting expanded like in a Unix shell, but it doesn't appear so, as echo * from cmd.exe results in a simple * output. I have also tried escaping the asterisk and enclosing it in quotes with arp -d "*" and arp -d ^*. Both result in the same error.

I do have two NICs on this machine, an internal and a USB, but I get the same error when I unplug the USB NIC.

The account I am running from is an administrator, and I have also tried right-clicking cmd.exe and selecting "Run as Administrator."

2 Answers

Use the command netsh interface ip delete arpcache

You can then run arp -a to confirm that the entries have gone.

Clear, Delete and Refresh ARP Cache Entry

I tried delete the ARP Cache with the arp -d command and showed me "The ARP entry deletion failed: The parameter is incorrect" then I tried with netsh interface ip delete arpcache command and it worked and then I tried with the arp -d command again and it worked.