UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): March 20, 2012

Quest Software, Inc.

(Exact name of registrant as specified in charter)

5 Polaris Way

Aliso Viejo, California 92656

(Address, including zip code and telephone number, including area code, of registrant’s principal executive offices)

Registrant’s telephone number, including area code (949) 754-8000

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On March 20, 2012, the special committee composed of independent and disinterested members of the Board of Directors of Quest Software, Inc., a Delaware corporation (“Quest” or the “Company”), approved a one-time cash payment (the “Retention Payment”) of $100,000 to Scott J. Davidson, Quest’s Senior Vice President and Chief Financial Officer. The Retention Payment is designed to encourage Mr. Davidson to continue to focus on the best interests of Quest’s stockholders following the execution of the Agreement and Plan of Merger (the “Merger Agreement”) on March 8, 2012 among Quest, Expedition Holding Company, Inc., a Delaware corporation (“Parent”), and Expedition Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Parent. The Merger Agreement was previously disclosed by Quest in a Current Report on Form 8-K filed with the Securities and Exchange Commission on March 9, 2012.

Subject to continued employment, the Retention Payment is payable following the earlier of (i) the Effective Time of the merger (as defined in the Merger Agreement) and (ii) the date of Quest’s entry into an agreement with respect to a Superior Proposal (as defined in the Merger Agreement).

Item 8.01 Other Events.

The information set forth above in Item 5.02 of this Current Report on Form 8-K is incorporated herein by reference.

Additional Information and Where to Find It

The Company intends to file with the Securities and Exchange Commission (the “SEC”) a proxy statement and intends to furnish or file other materials with the SEC in connection with the proposed transaction. The definitive proxy statement will be sent or given to the stockholders of the Company and will contain important information about the proposed transaction and related matters. BEFORE MAKING ANY VOTING DECISION, QUEST’S STOCKHOLDERS ARE URGED TO READ THE PROXY STATEMENT AND THOSE OTHER MATERIALS CAREFULLY AND IN THEIR ENTIRETY BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE COMPANY AND THE PROPOSED TRANSACTION. The proxy statement and other relevant materials (when they become available), and any other documents filed by Quest with the SEC, may be obtained free of charge at the SEC’s website at www.sec.gov. In addition, security holders will be able to obtain free copies of the proxy statement from Quest by contacting Quest’s Investor Relations by telephone at (949) 754-8000, or by mail at Quest Software, Inc., 5 Polaris Way, Aliso Viejo, California 92656, Attention: Investor Relations, or by going to Quest’s Investor Relations page on its corporate web site at www.quest.com.

Participants in the Solicitation

Quest and its directors and executive officers may be deemed to be participants in the solicitation of proxies from the stockholders of Quest in connection with the proposed merger. Information regarding the interests of these directors and executive officers in the transaction referenced herein will be included in the proxy statement described above. Additional information regarding these directors and executive officers is included in Quest’s proxy statement for its 2011 Annual Meeting of Stockholders, which was filed with the SEC on April 28, 2011.

Forward-Looking Statements

This filing may include predictions, estimates and other information that might be considered forward-looking statements, including, without limitation, statements relating to the completion of the merger. These statements are based on current expectations and assumptions that are subject to risks and uncertainties. Actual results could differ materially from those anticipated as a result of various factors. If the transaction is consummated, the Company’s unaffiliated stockholders will cease to have any equity interest in the Company and will have no right to participate in its earnings and future growth. Additional factors that may affect the future results of the Company are set forth in its filings with the SEC, including its Annual Report on Form 10-K for the year ended December 31, 2011, which is available on the SEC’s website at www.sec.gov. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date thereof. The Company undertakes no obligation to update forward-looking statements to reflect events or circumstances after the date thereof.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.