I'm continuing to receive these warning messages when the extender is switched on. I'd really appreciate some help with this!

Many thanks Joseph. Inevitably, the fault doesn't happen continually, and now I want it show up, so far it hasn't! I'm all set to get a screenshoot as soon as it does.

To answer your other queries in the meantime:

The PC (which is not an off-the-shelf model) is running Windows 10, and is already connected to the router via ethernet. The TP extender is of course picking up the WiFi transmission from the router.

The router is a Technicolor DGA0122NLK.
The main purpose of the extender is to enable us to use iPlayer etc on our TV at the far end of the house. It's very successful at this - more so than the Powerline Adaptor we were using previously, and which has just failed.

As mentioned I'm currently only switching on the extender when we need to use the TV on catch-up.

The security software is ESET Smart Security Premium and it's this which has been reporting the malicious traffic (which it has blocked).

These error messages only started appearing after the TP-Link extender had been installed so I naturally assumed this was the source of the problem. however it may turn out that it's not the cause.

I'll open discussion with ESET as well in case they can help.

If it does continue happening I'll send the screen shot as promised.

Hi Joseph

The Malicious Traffic message has occurred a couple of times and I managed to take the attached screenshot. I hope this gives a clue as to what is happening. I always find that switching off the extender stops the messages from popping up every couple of minutes.

I've read that TP-Link extenders are vulnerable to hacking and this has me worried, as you can imagine!

Thanks

David

  @DavidMW This problem has continued and is now happening frequently. I've had lengthy conversations with ESET whose internet security software I'm using and it seems very clear that the TP-link TL-WA850RE is the source of the problem. I'm getting two warning messages, one mentions duplicate IDs, the other refers to ARP cache poisoning attacks. Mostly the IP address quoted in the warnings is192.168.1.1 which is the router ID. I've tried setting a fixed IP (different) for the extender but that didn't help.

I'm wondering if it needs a firmware update? I don't want to power it up any longer than necessary - how do I find what version firmware it has?

Please help as I can't use it at all as it is!

In the absence of any further guidance I decided to stop using the TL-WA850RE altogether and replace it with a Netgear equivalent. This has solved the problem entirely.

Normally I would recycle unwanted gear but I don't feel comfortable passing this device on to anyone else so I think a hammer is called for.

  @Joseph-TP

I'm sorry to say the extender persisted in causing the Malicious Traffic warning messages despite considerable help from ESET (manufacturer of the Internet Security software). I tried many tricks to tackle the problem but none of them succeeded.

I've bought a Netgear extender which is working beautifully.