Authentidate Holding Corp. to Report First Quarter 2008 Results on Tuesday, November 6, 2007

BERKELEY HEIGHTS, N.J.
Oct 25, 2007

Authentidate Holding Corp. (Nasdaq: ADAT), a worldwide provider of software and web-based services that enable enterprises and individuals to exchange information securely and conduct trusted business transactions, today announced that it plans to report financial results for the first quarter ended September 30, 2007 on Tuesday, November 6, 2007 after the close of market trading.

Management will host a conference call at 4:30 p.m. ET on Tuesday, November 6, 2007, to discuss the latest corporate developments and results. The dial-in number for callers in the U.S. is (888) 694-4676 and the dial in number for international callers is (973)-582-2737. The access code for all callers is 9353215. To access the live webcast, visit www.authentidate.com, click the "About Us" link, followed by "Investor Relations" on the drop-down menu and then the "Audio Archives" link. Following the conclusion of the call, the webcast will also be archived on the Company's website.

A replay of the call will be available through November 13, 2007. To access the replay, please dial (877)-519-4471 in the U.S. and (973)-341-3080 internationally, and then enter the access code 9353215. A live webcast will be available on the Company's website.

About Authentidate Holding Corp.
Authentidate Holding Corp. is a worldwide provider of software and web- based services that enable enterprises and individuals to exchange information securely and conduct trusted business transactions. Our offerings are targeted at enterprises and office professionals, and incorporate security technologies such as electronic signing, identity management, and content authentication to electronically facilitate secure and trusted transactions. In the United States, we also offer our proprietary and patent pending content authentication technology as a web-based service in the form of the United States Postal Service(R) Electronic Postmark(R).

The company operates its business in the United States and Germany. For more information, visit the company's website at http://www.authentidate.com.

This press release contains forward-looking statements within the meaning of section 27A of the Securities Act of 1933 and section 21E of the Securities Act of 1934. When used in this release, the words "believe," "anticipate," "think," "intend," "plan," "will be," "expect," and similar expressions identify such forward-looking statements. Such statements regarding future events and/or the future financial performance of the Company are subject to certain risks and uncertainties, which could cause actual events or the actual future results of the Company to differ materially from any forward-looking statement. Such risks and uncertainties include, among other things, the availability of any needed financing, the Company's ability to implement its business plan for various applications of its technologies, related decisions by the USPS, the impact of competition, the management of growth, and the other risks and uncertainties that may be detailed from time to time in the Company's reports filed with the Securities and Exchange Commission. In light of the significant risks and uncertainties inherent in the forward-looking statements included herein, the inclusion of such statements should not be regarded as a representation by the Company or any other person that the objectives and plans of the Company will be achieved.

Source: Authentidate Holding Corp.

Authentidate® is a registered trademark of Authentidate Holding Corp.