Mistake: postback rejected by IP whitelist mismatch

Mistake: postback rejected by IP whitelist mismatch

Failure mode: your tracker accepts postbacks only from whitelisted network IPs (good practice). The network then sends from a new IP range or a different sending server, your tracker silently rejects the postbacks, and conversions disappear with no error you ever see.

Fix — 5 steps:
— Get the network's current postback-sending IP ranges in writing and load them into the tracker whitelist.
— Re-confirm those ranges quarterly — networks migrate infrastructure without announcing it.
— Enable logging of rejected postbacks. Silent rejection with no log is how this stays invisible for weeks.
— Pair IP whitelisting with a shared secret token in the postback URL so you can loosen IP rules without losing security.
— When conversions drop to zero overnight with stable traffic, check the rejection log first, before blaming the offer.

Verify: ask the network to fire a test postback from production infrastructure. It must be accepted and logged, not rejected.

Save this SOP. Run this before every launch.