Multiple display URL domains in one ad group (reason 8159)

Ads in a single ad group must share one display URL domain; you have ads pointing to multiple distinct root domains in the same group.

Microsoft Merchant Center validates landing-page URLs for crawlability, format, and uniqueness. Common triggers: invalid characters, relative paths, missing protocol, redirect chains, or hostnames that don't resolve.

1. Test the URL in a private/incognito browser — if it doesn't load instantly, the channel can't load it either.
2. Confirm protocol is `http://` or `https://`. Most channels prefer HTTPS.
3. URL-encode special characters (spaces → %20, ampersands → %26).
4. Eliminate redirect chains — most channels allow max 2 redirects.
5. Remove user-specific tracking parameters from product URLs.

• Hash fragments (#section) — typically stripped, leaving the rest valid only if structurally OK
• WAF rules blocking the channel's crawler — whitelist by IP range or user-agent