Can I “reactivate” dead lists safely?

With Great Caution. Reactivating dead lists is risky but sometimes possible with careful approach. The older and more dormant the list, the higher the risk of spam traps and bounces.

Start with validation services to remove invalid addresses. Send in very small batches, monitoring carefully for bounces, complaints, and engagement. Any negative signals should stop the process immediately.

Honest messaging helps. Acknowledge the lapse and give clear opportunity to re-opt in or opt out. Those who positively engage can be added back gradually. But expect significant list shrinkage.