@ChetanK 

Hi， For Deco M4, it does not support the Antivirus feature;

May I know what are these websites have been blocked?

Did all the clients fail to access these websites?

And have you set up any parental control rules for the devices?

Thank you very much.

@TP-Link Hi!

Some websites which are blocked are:

https://snahp.it/

https://forum.snahp.it/index.php

https://proxyrarbg.org/torrents.php

and some others too.

Yes, I've tried a few devices. They don't work on them too. 

I don't want to block any websites whatever they are, so I've changed the dns too. But, the websites are still blocked.

No, I've not set up any parental control rules whatsoever.

Hoping for a quick resolution.

Thanks!

@ChetanK 

Thanks for the update.

Since you mentioned if the devices are connected to the ISP mode, these websites work fine;

Have you tried to copy the DNS settings at the moment and put it under IPV4?

https://www.tp-link.com/support/faq/1855/ 

In case the above situation did not make any difference, can I have a picture of the error message when you failed to access these websites?

@TP-Link the link which you've send is dead. Can you send a different link?

@ChetanK 

Sorry and I updated the link again; you could have a try again now;

Thank you.