Ads galore on devices after installing. Is this to be expected? Does it need to run a few days?

[deHakkelaar]

If there is no IPv6 solution for this type of modem, try enable below option:

But dont enable below one:

And let Pi-hole take over DHCP for your network:

How do I use Pi-hole's built in DHCP server (and why would I want to)?

Using Your Existing Router For Network-wide Ad Blocking You might not need to use Pi-hole's DHCP server: In many home environments, your router also functions as your DHCP server. In this case, you can often set Pi-hole to be the DNS server for your network clients in the router's DHCP (or LAN) settings page, which allows all of your network clients to block ads simply by connecting to the network. Setting it up this way is also what makes Pi-hole very powerful for network-wide ad blocking. …

Copy IP range and gateway from the router DHCP settings over to Pi-hole.
Release DHCP lease on the Win PC:

ipconfig /release

And renew:

ipconfig /renew

And check DNS servers assigned:

ipconfig /all

EDIT: ow is better to enable Pi-hole DHCP first before disabling the router DHCP!
EDIT2: ow and disable as many IPv6 settings on the LAN side as possible (dont touch the WAN/Internet settings) !