DECISION ORDER
ORDERED that the order is affirmed insofar as appealed from, with one bill of costs payable to the respondents appearing separately and filing separate briefs.
The demand pursuant to CPLR 3216 attached to the compliance conference order dated March 28, 2000, and signed by counsel for all parties, constituted a valid 90-day notice pursuant to CPLR 3216 ( see Apicella v. Estate of Apicella, 305 A.D.2d 621, lv denied 100 N.Y.2d 513; Aguilar v. Knutson, 296 A.D.2d 562; Flomenhaft v. Baron, 281 A.D.2d 389). Contrary to the plaintiff's contention, failure to serve a CPLR 3216 90-day notice by certified or registered mail is a procedural irregularity, and, absent a showing of prejudice to a substantial right of the plaintiff, should not result in vacating a dismissal of the action ( see Balancio v. American Opt. Corp., 66 N.Y.2d 750, 751; Yi Pao Lu v. Scaduto, 303 A.D.2d 750). Here, having received a 90-day notice, the plaintiff was required either to timely file a note of issue or to move, before the default date, to vacate the notice or to extend the 90-day period ( see Apicella v. Estate of Apicella, supra; Yi Pao Lu v. Scaduto, supra; Aguilar v. Knutson, supra).
After the plaintiff failed to comply with the demand, the Supreme Court, on its own initiative, dismissed the complaint pursuant to CPLR 3216 on January 19, 2001. Over a year later, the plaintiff moved, in effect, to vacate the dismissal, and was required to establish a reasonable excuse for noncompliance with the demand and a meritorious cause of action ( see Sustad v. Karagiannis, 305 A.D.2d 664; Vento v. Bargain Bilge W., 292 A.D.2d 596; Werbin v. Locicero, 287 A.D.2d 617). Since the plaintiff failed to establish a reasonable excuse, the court properly denied his motion, in effect, to vacate the dismissal.
PRUDENTI, P.J., H. MILLER, SCHMIDT and COZIER, JJ., concur.