—Order unanimously modified on the law and as modified affirmed without costs in accordance with the following Memorandum: Supreme Court properly denied plaintiff’s motion for partial summary judgment on the first cause of action but erred in denying defendant’s cross motion for summary judgment dismissing the first through fourth causes of action. Defendant met its burden of establishing its entitlement to judgment as a matter of law by submitting evidentiary proof in admissible form showing that the failure of the drainage pipes was caused by errors in the installation of the pipes or in the design of the project and not by the alleged failure of the pipes to conform to contract specifications. The burden then shifted to plaintiff to produce evidentiary proof in admissible form sufficient to defeat the cross motion (see, CPLR 3212 [b]; Zuckerman v City of New York, 49 NY2d 557, 562). The conclusory, unsubstantiated assertions contained in the affidavit of plaintiff’s president are insufficient to meet that burden (see, Zuekerman v City of New York, supra, at 562). Further, the un*1019sworn letters, memoranda and reports submitted by plaintiff are not proof in admissible form (see, Grasso v Angerami, 79 NY2d 813, 814; Briggs v Consolidated Rail Corp., 190 AD2d 1047, 1048), and plaintiff has offered no acceptable excuse for its failure to obtain statements in admissible form from the authors of those documents (see, De Thomasis v Riccardi, 194 AD2d 849, 849-850). Plaintiffs "expressions of hope” that the documents may qualify for admission as business records (see, CPLR 4518), unsupported by any facts establishing a foundation for their admissibility, are insufficient to defeat defendant’s cross motion (Zuckerman v City of New York, supra, at 562; see, Doliendo v Johnson, 147 AD2d 312, 321).
We modify the order on appeal, therefore, by granting defendant’s cross motion for summary judgment dismissing the first through fourth causes of action. (Appeals from Order of Supreme Court, Monroe County, Frazee, J. — Summary Judgment.) Present — Green, J. P., Lawton, Callahan, Doerr and Davis, JJ.