The board found that appellant State Insurance Fund did not properly cancel the employer's insurance policy. We agree. Proper cancellation of the policy in question requires, inter alia, that a notice of cancellation be "served on the employer by delivering it to him or by sending it by mail, by certified or registered letter, return receipt requested" (Workers' Compensation Law, § 54, subd 5). And, "[f]or obvious reasons of public policy underlying the very structure of the [Workers'] Compensation Law a policy may only be cancelled in strict conformity with the statute" ( Matter of Horn v. Malchoff, 276 App. Div. 683, 685, mot for lv to app den 301 N.Y. 814; see, also, Matter of Fromer v. John St. Serv. Center, 34 A.D.2d 1081). In the present case, the sole evidence that a notice of cancellation was sent to the employer is a mailing manifest which shows that a piece of certified mail was sent to the employer. However, there is nothing in the manifest or the record which demonstrates that a cancellation notice was in fact sent to the employer. Furthermore, contrary to the State Insurance Fund's assertion, the presumption of regularity does not arise in this case as no proof of office practice was offered (see Nassau Ins. Co. v. Murray, 46 N.Y.2d 828). Decision affirmed, with costs to the Uninsured Employers' Fund. Kane, J.P., Main, Mikoll, Weiss and Levine, JJ., concur.