False negatives and positives (ads)

[deHakkelaar]

@marwan

Only some ads seem to be blocked. The Pi-hole interface says that it is blocking queries, however, Google and YouTube ads still appear.

Those are close to impossible to block with just Pi-hole as most of the ads come from the same domain as the actual content is coming from.
Search here on discourse to see the many attempts.

@marwan

I’m getting false positives. Email newsletter links are being mistaken as ads.

Below might be useful to see if any is being blocked that shouldn't:

How do I determine what domain an ad is coming from?

Block ads or fix broken sites This FAQ is written in the context of finding out how to block an ad that isn't blocked automatically, but the same steps can be used to troubleshoot issues with sites that don't function properly. An example is that sometimes certain payment gateways try to collect metrics on the sale, but these domains are blocked by Pi-hole, so the payment cannot be processed. Also, some links send you through several referrers and if one of them is blocked, you may land on a …

@marwan

Just to clarify, is Pi-hole supposed to block all ads or some of them? And are false positives common?

Depends what block lists you use/configured.
Some lists might be over zealous.