QBD 20 March 1999. The defendants (M) were lessees of business premises for a term of 20 years, but assigned the lease to T. The lease was subsequently forfeited for arrears of rent, and the solicitors for the plaintiffs (C) sent M a notice under the Landlord and Tenant (Covenants) Act 1995 s17 claiming arrears of rent, service charge and insurance premiums. The notice was sent by recorded delivery to the last known abode of M, but was returned by the Post Office undelivered. The notice contained an error in the way interest on rent arrears was calculated, and an application for summary judgement and a determination of a point of law was originally dismissed on the grounds that the notice had not been validly served. C appealed. "Held" Appeal allowed. A notice under s17 was validly served if it is sent by recorded delivery to the recipient at his last known address, whether it is received by the recipient or not. The error in the notice did not affect the claim for arrears of rent.