Recovery certificates: withhold enforcement when payment is claimed and verify dues before coercive tax collection. Recovery certificates must not be issued or enforced where the tax demand has been paid or is claimed to have been paid; enforcement should be withheld until the Certificate Officer hears from the Income Tax Officer. Administrative steps are required to cancel infructuous certificates, ensure accurate entries of payments and appeal reductions in the Demand and Collection Register with proper challans, and to restrict coercive measures to cases where tax is genuinely due. Officials who cause harassment through negligence must be corrected. Attachment of known third party debts is recommended to secure collection and protect limitation rights.