Symantec Is Not Sweating Microsoft's Vista

Still, one analyst at the conference said Thompson was overestimating the impact of marketing and branding initiatives vs. the Microsoft challenge. "There's no hard, concrete substance behind that," said Graham Titterington, an industry analyst with Ovum in London.

He said Microsoft will accelerate Symantec's move toward the enterprise, and noted that with the acquisition of Veritas, the company seems to be repositioning itself beyond just traditional security products.

Thompson also addressed the company's clash with the Internal Revenue Service about $1 billion in back taxes related to the Veritas deal.

He called the situation "an open dispute with the IRS," and added that "we are running the business assuming that will go away."

Titterington predicted that Symantec will announce a partnership in the identity and access-management area, where Symantec is lacking. (Titterington and his company are independent and do not have a financial relationship with Symantec or Microsoft.)

Shares of the security firm closed down 2.1%, or 38 cents, to $17.38. It gained a penny after-hours. Symantec will post its fourth-quarter earnings on Tuesday after the bell.