IRVINE, Calif., July 20, 2005 – Quest Software Inc. (Nasdaq: QSFT), a leading provider of application, database and infrastructure management solutions, today announced general availability of Quest InTrust for Active Directory version 1.6, which now offers full Active Directory and domain controller activity tracking, in addition to previously available Active Directory change auditing functionality. The product, formerly known as Change Manager for Active Directory, is part of the Quest Compliance Suite for Windows, also announced today.

InTrust for Active Directory automates the collection of event log data on Active Directory domain controllers, analyzes and reports on events and system changes, and then archives the data in an efficient and manageable way. The product equips administrators to track activity such as user logons and attempts, user and group management, user rights management, as well as changes to policy and changes to all critical objects in Active Directory.

“This combination of functionality offers more benefit than other products, which provide only change tracking capability,” explained Betsy Bender, director, Active Directory solutions, Quest Software. “InTrust for Active Directory allows organizations to efficiently audit unusual user and administrator activity, track security events and gain control of domain controller event logs throughout the enterprise. The result is more complete security auditing on the most critical servers – the domain controllers.”

New audit-related features in InTrust for Active Directory include:

• Smart event data analysis – Event correlation and anomaly detection help maintain security by identifying potential problems and notifying IT personnel immediately when activity patterns match customer-defined criteria.
   

• Enhanced user interface – An improved administrator interface streamlines deployment and simplifies data analysis by offering both alerts and reports from a single console.
   

• Advanced search capabilities – Improved navigation and flexible searching of event alerts provides administrators with quicker access to audit data.

`Previously, our attempts to document and archive all changes to Active Directory with native tools proved onerous. With this product, we gain comprehensive auditing of all changes to Active Directory. We can also be confident that we are protecting our environment by automatically taking corrective action for undesired changes,` said Graham Drinkwater, IT manager, Landmarc Support Services.

Pricing and Availability
North American pricing for InTrust for Active Directory begins at $12 U.S. per user account. To learn more about the Quest Compliance Suite for Windows and to download the software, visit http://wm.quest.com/products/compliance.

About Quest Infrastructure Management
Quest Software, Microsoft’s 2004 Global Independent Software Vendor Partner of the Year, provides solutions that simplify, automate and secure Active Directory, Exchange and Windows, as well as integrate Linux and Unix into the managed environment. Quest’s Infrastructure Management products deliver comprehensive capabilities for secure management, migration and integration of the heterogeneous enterprise. For more information on Quest Software’s Infrastructure Management solutions, please visit www.quest.com/microsoft.

About Quest Software, Inc.
Quest Software, Inc. delivers innovative products that help organizations get more performance and productivity from their applications, databases and infrastructure. Through a deep expertise in IT operations and a continued focus on what works best, Quest helps more than 18,000 customers worldwide meet higher expectations for enterprise IT. Quest Software, headquartered in Irvine, Calif., can be found in offices around the globe and at www.quest.com.

Quest and Quest Software are registered trademarks of Quest Software, Inc. The Quest Software logo and all other Quest Software product or service names and slogans are registered trademarks or trademarks of Quest Software, Inc. All other trademarks and registered trademarks are property of their respective owners.

Forward Looking Statements
This release may include predictions, estimates and other information that might be considered forward-looking statements, including statements concerning the availability and market acceptance of our new version of Quest InTrust for Active Directory. These statements are based on current expectations and assumptions that are subject to risks and uncertainties. Actual results could differ from those anticipated as a result of various factors, including the impact of economic conditions on our customers, variations in the size and timing of customer orders; competitive products and pricing; rapid technological change; risks associated with the development and market acceptance of new products; disruptions caused by acquisitions of companies and/or technologies including risks relating to integration of the combined companies; risks associated with international operations; and the need to attract and retain qualified personnel. For a discussion of these and other related risks, please refer to our recent SEC filings, including our Annual Report on Form 10-K for the year ended December 31, 2004 and the Current Report on 10-Q for the quarter ended March 31, 2005. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date thereof. We undertake no obligation to update forward-looking statements to reflect events or circumstances after the date thereof.