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What: Shares of security-software specialist Symantec (Nasdaq: SYMC) got crushed today, down by as much as 12%, after the company released preliminary estimates of fourth-quarter earnings.

So what: Revenue should be about $1.68 billion, lower than the company's own guidance of around $1.72 billion, which is also roughly what the Street was expecting. Adjusted earnings per share should land at $0.38, also lower than hoped.

Now what: CEO Enrique Salem said a larger than expected portion of enterprise subscription contracts resulted in higher deferred revenue. In addition, license performance was soft because of fewer storage and server management deals. Symantec is set to report its official results on May 2, but don't expect them to be much different.

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Fool contributor Evan Niu holds no position in any company mentioned. Check out his holdings and a short bio. The Motley Fool has a disclosure policy. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days.