Shares of Dell ( DELL) were among technology's losers Friday, slumping 11% after the computer giant warned that second-quarter results would be below Wall Street's forecast. The company expects to post earnings of 21 cents to 23 cents a share on revenue of about $14 billion. Analysts polled by Thomson First Call project earnings of 32 cents a share on revenue of $14.23 million. Dell, which had issued a similar warning after the first quarter, said the weaker-than-expected guidance reflects "aggressive pricing in a slowing commercial market worldwide." Dell plans to issue second-quarter results on Aug. 17. Shares were recently trading down $2.46 to $19.64. Microsoft ( MSFT) rose 4% after the company posted better-than-expected fourth-quarter earnings and announced a big tender offer and buyback plan. For the quarter ended June 30, the software giant earned $2.83 billion, or 28 cents a share. Results included a one-time charge of 3 cents a share. Without the charge, the company would have earned 31 cents a share, topping analysts' average estimate by a penny. Microsoft posted revenue of $11.8 billion, above Wall Street's projection of $11.63 billion. During the year-earlier quarter, the company earned $3.7 billion, or 34 cents a share, on revenue of $10.16 billion. Microsoft also announced a $20 billion tender offer, which will be completed on Aug. 17, the company said. The company will buy shares at prices ranging from $22.50 to $24.75 a share. Additionally, Microsoft said that it would buy $20 billion in stock as part of a repurchase program. The buyback program will expire on June 30, 2011. "With our share repurchase programs announcement today, we reaffirm our confidence and optimism in the long-term future of the company and continue to execute on our strategy of returning capital to shareholders," the company said. Shares were up 95 cents to $23.80.