About ARP: ARP, which abbreviates for Address Resolution Protocol, is an efficient technique to map Network Layer addresses to its equivalent Data Link Layer addresses. In simpler terms, it is a direct linking between addresses of Data Link Layer (which are mostly MAC addresses) and Network Layer (which we term as IP addresses).
Issues with and symptoms of damaged ARP Cache
ARP cache is likely to become damaged at times, which may need a reset or clearance. This problem may have an effect on the functional operations of your Windows operating system and connectivity to the Internet. For example, your webpage loading may timeout and the page may not open. Also at times, you may able to ping your own IP address and 127.0.0.1, but pinging other IP addresses won’t work.
Clear ARP Cache
An easy solution to the above problem is to clear the ARP cache. To take a look at the present ARP Cache, open Command Prompt and type arp -a command. It will give you a list of addresses mapping.
Now, to clear the ARP cache we use the netsh command as follows,
netsh interface ip delete arpcache
The above command requires the user to be in administrative mode. If you aren’t, it will throw an error like “The requested operation requires elevation (Run as administrator)“.
To start the Command Prompt in “administrative mode”, open the Search programs dialog (not Run dialog) in the Start Menu, type cmd or cmd.exe and press [CTRL]+[SHIFT]+[ENTER] together. This will start the Command Prompt in administrative mode (Administrator will be written in the window’s titlebar).
Now, retype the command netsh interface ip delete arpcache and press Enter. If everything works well, it will simply say Ok.
At times, while clearing the ARP cache, it may encounter an error. This error is mainly due to the enabled state of Routing and Remote Access service. You can rerun the netsh command after disabling the service. In order to disable the Routing and Remote Access service, follow the below steps:
- Goto Start Menu > Run prompt and type services.msc. Press Enter.
- Search for Routing and Remote Access service. Double-click it.
- In the Properties box, if the Service status is Started, click Stop button. Change Startup type to Disabled. Click Apply and then OK.
Now, type netsh interface ip delete arpcache again in the Command Prompt (with administrative privileges) and it should successfully clear the ARP cache.
Were you able to successfully clear ARP cache in your computer or did you confront an issue?