The Dow Jones Industrial Average (^DJI -1.24%) was off to a good start on Friday, rising more than 40 points as of 11:30 a.m. EST. Microsoft (MSFT -1.41%) was one of the index's biggest gainers, likely helped out by former Dow Jones component Hewlett-Packard's (HPQ -2.40%) earnings report. Groupon (GRPN -3.08%) was a notable underperformer, tumbling early in the session.

Existing home sales disappoint
The Dow Jones' rally stood in spite of disappointing data released on U.S. home sales. Total existing home sales came in at a seasonally adjusted annual rate of 4.62 million in January, less than the 4.68 million sales that economists had anticipated. On a month-over-month basis, home sales slid 5.1%. Economists had expected a 4.3% decline.

The numbers released on Friday backs up data released earlier in the week suggesting that the U.S. housing market appears to be weakening. Nevertheless, investors don't appear to be overly worried, perhaps attributing the weakness to weather.

Hewlett-Packard says PC market improving
Hewlett-Packard shares were down nearly 2% early on Friday, as investors reacted to the company's earnings report. While Hewlett-Packard beat analyst expectations on both revenue and profit, it gave guidance that was a bit disappointing. For the coming quarter, Hewlett-Packard expects to report earnings of between $0.85 and 0.89 per share; analysts had been looking for $0.89 per share.

Meanwhile, Microsoft shares rose more than 1%, likely because of comments Hewlett-Packard's CEO, Meg Whitman, made during the HP earnings call.

Although the PC market contracted severely in 2013, the slowdown appears to be moderating. Hewlett-Packard's personal systems group, which includes traditional PCs that use Microsoft's Windows, actually grew last quarter. Whitman attributed the growth to businesses, which continue to rely on traditional PCs to get work done.

While tablets and mobile devices have put immense pressure on the market for Microsoft's operating system, Windows should preserve on the strength of enterprise demand.

Groupon obliterated on guidance debacle
Shares of Groupon were down more than 17% in early trading. Although Groupon's quarterly earnings and revenue exceeded analyst expectations, its guidance was immensely disappointing. 

Next quarter, Groupon expects to lose $0.02-0.04 per share; analysts had been looking for the company to profit about $0.06 per share. Groupon did give a revenue forecast that was above analyst expectations, but investors appeared to be focusing on that loss estimate, as shares shed nearly one-fifth of their value early on Friday.