CPLR § 3012(d)

CPLR § 3012. Service of pleadings and demand for complaint

(d) Extension of time to appear or plead

Nolan v Lechner, 2009 NY Slip Op 01724 (App. Div., 1st, 2009)

A party who has commenced an action by service of a summons without
complaint and fails to serve a complaint within 20 days of a demand
must demonstrate the merits of the action and a reasonable excuse for
the delay in order to avoid dismissal
(CPLR 3012[d]; Barasch v Micucci, 49 NY2d 594, 599 [1980]).

Plaintiff did satisfy these requirements. On May 1, 2007,
defendants served a notice of appearance and demanded a complaint,
which meant that plaintiff had 20 days in which to comply (CPLR
3012[b]). On June 26, 36 days after expiration of the 20-day deadline,
plaintiff served a copy of the verified complaint, attached as an
exhibit to her cross motion to compel defendants' late acceptance of
the complaint (see 3012[d]). Plaintiff's counsel cited law
office failure for the delay, claiming to have discovered on June 1
only defendants' notice of
appearance, but not their demand; also cited was the disabled
plaintiff's physical difficulties in appearing at counsel's office to
sign the verification. This constituted a reasonable excuse for the
(see Wess v Olympia & York Realty Corp., 201 AD2d 365 [1994]).

Plaintiff also submitted an affidavit of merit, sufficiently
detailing the injuries she allegedly suffered as a result of
defendants' tortious acts.
At no time did plaintiff evince an intent to
abandon her claim, and defendants have not demonstrated prejudice by
reason of the delay (see Rose v Our Lady of Mercy Med. Ctr., 268 AD2d 225 [2000]).

Dismissal of the action under these circumstances was an improvident exercise of the court's discretion (see Aquilar v Nassau Health Care Corp., 40 AD3d 788 [2007]).

The bold is mine.