Key Messages & Handling Customer/Partner Questions Sept 2007 Zimbra Confidential

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.2Copyright © 2007 Zimbra, Inc.

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.3Copyright © 2007 Zimbra, Inc. Key Message 1: Continuity No change to product editions; fully committed to on-prem & hosted solutions No change to product packaging & pricing No change in Zimbra support processes No change to Zimbra team No change to ZCS 5.0 plan & release timeline No change to our commitment towards customers & partners (incl HSPs) No change to community commitment and source code availability No change to sales processes

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.4Copyright © 2007 Zimbra, Inc. Key Message 2: 1+1 = 3! Worldwide reach & brand awareness Resources & investment to build more powerful innovative experiences Potential for tie-in(s) with Y! content and other technology assets to add to end-user productivity and alternative monetization options (only if required) Customers need not be concerned about small company survival/viability over long-term

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.5Copyright © 2007 Zimbra, Inc. Leveraging Yahoo! Strengths 10 years of global leadership & expertise in mail and communication; 250M mail users Extensive understanding of end-user needs and experiences Many assets (e.g. Travel, Finance) in Y! network for one-click access to important info for business users and consumers alike Y! commitment to Openness & Choice! Brand and worldwide reach, investment and support

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.6Copyright © 2007 Zimbra, Inc. Q&A and Objection Handling But, Yahoo is a consumer company… Zimbra enables Y! to enter new markets and leverage its global reach and investment potential Y! excited about Biz, EDUs, SP partnerships Y! offers a co-branded version of Mail today through its broadband partnerships Y! also has a small business product/business for SMBs which will evolve to offer best of breed products Y! has relationships with many ISPs due to its ad network Will the Zimbra server and web client remain open source? Zimbra remains committed to open source community Access to Zimbra source code will remain available and free (stop here )

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.7Copyright © 2007 Zimbra, Inc. Q&A and Objection Handling Will I be able to provide input on new enhancements and bugs like I did before? Absolutely. Y! committed to community development model & transparency No change to bugzilla, pm.zimbra or the voting process No change to forums or community participation Will Yahoo! offer a hosted solution too? If so, why would HSPs want to host Zimbra anymore? Yahoo! will continue to operate Yahoo! Mail – including both free and premium consumer services Plan is to extend web mail experience for both partners & audiences to reach out to more people at school, work and home Channel sales for SaaS - offering coming soon Yahoo! is committed to Zimbras partners - VARs & HSPs

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.8Copyright © 2007 Zimbra, Inc. Q&A and Objection Handling Will the Zimbra commitment to multiple platforms or apps (e.g. Outlook) change? No. Yahoo! is committed to customer and end-user choice We will continue to offer solutions for on-prem deployments If anything, we will improve our compatibility story thanks to the Yahoo! brand and relationships with major industry players Will there be any impact to support during the integration No. We expect integration to be quick During the process, the support and engineering teams will continue to operate as per the current plans There are no expected personnel changes

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.9Copyright © 2007 Zimbra, Inc. Resources for more information Zimbra website to be updated Satishs blog – Why Yahoo!, Zimbra synergies Press release – quotes from Jerry, Brad & Satish Brads quote on web site "The entire Yahoo! team is excited to embrace Zimbra's customers, partners and community and I want to personally welcome them to the Yahoo! family, said Brad Garlinghouse, senior vice president, communications and communities, Yahoo! Inc. "We are committed to building on Zimbra's success and to investing in both Zimbra's on- premise and SaaS product offerings." Q&A – answers many questions on how this impacts existing customers/partners Support page announcement

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.10Copyright © 2007 Zimbra, Inc. More outreach tomorrow Customer & partners blast (~2K) Prospects blast (~45K) Call list to chat with select customers and partners Satish meets with press (WSJ, NYT, Reuters, CNET)

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.11Copyright © 2007 Zimbra, Inc.

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.12Copyright © 2007 Zimbra, Inc. Questions?

Zimbra, Zimlets, and the Zimbra logos are registered trademarks of Zimbra, Inc. All other trademarks are property of their respective owners.13Copyright © 2007 Zimbra, Inc. Thank you!