Ordered that the judgment is affirmed insofar as appealed from, with costs.
It is well settled that summary judgment is appropriate only where a thorough examination of the merits clearly demonstrates the absence of any triable issues of fact (see, Marine Midland Bank v. Dino Artie's Automatic Transmission Co., 168 A.D.2d 610). In the instant case, the appellant neither denied having executed an unlimited continuing guarantee nor claimed that she gave written notice of its termination (see, Marine Midland Bank v Dino Artie's Automatic Transmission Co., supra, at 610). While she does claim that the guarantee was orally modified, the guarantee specifically provided that it could only be revoked by a writing. Thus the appellant continued to remain legally obligated as a guarantor, absent proper revocation (see, Chemical Bank v. Sepler, 60 N.Y.2d 289, 294; Chemical Bank v Wasserman, 37 N.Y.2d 249, 252; Bank of N.Y. v. Kranis, 189 A.D.2d 741; Bank of N.Y. v. LoFaso, 159 A.D.2d 475; Norstar Bank v Prompt Process Serv., 117 A.D.2d 589, 590).
Nor do the facts justify the application of the doctrine of estoppel, as there is no evidence that the bank assured either the appellant or any of her co-guarantors that the guarantee was no longer in effect, despite its request for additional guarantees (see, Marine Midland Bank v. Dino Artie's Automatic Transmission Co., 168 A.D.2d 610, 610-611, supra; Nanuet Natl. Bank v. Rom, 96 A.D.2d 898).
We have reviewed the appellant's remaining contentions and find them to be without merit. Sullivan, J.P., Lawrence, Pizzuto and Friedmann, JJ., concur.