* HP shares up after announcing plans to cut jobs
* NetApp shares slide nearly 15 pct, warns on Europe
* Airlines rally on JPM price hikes
* Indexes down: Dow, S&P 0.3 pct, Nasdaq 0.7 pct
NEW YORK, May 24 (Reuters) - U.S. stocks fell on Thursday on ongoing concerns about Greece's possible exit from the euro zone, while tepid U.S. economic data gave investors little reason to take risk.
Declines in technology stocks, led by a nearly 15 percent drop in NetApp Inc, weighed the Nasdaq further.
Data showed demand for long-lasting U.S. manufactured goods rose less than expected in April while weekly jobless claims dipped modestly for the week ended May 19.
"On both the job front and durable goods orders (data) was a little bit disappointing but not outright negative," said Bruce McCain, chief investment strategist at Key Private Bank in Cleveland, Ohio.
"The market has pulled back far enough that people are trying to assess if we've priced the worst of what's known. But with the problems in Europe and the fact the news isn't reassuring, prices are still somewhat soft."
Underscoring the vulnerability of corporate America to events in the euro zone, NetApp on Wednesday forecast revenue below Wall Street's expectations and its chief executive warned about uncertainty in Europe. The data storage equipment maker's shares tumbled 14.7 percent to $28.03.
The Dow Jones industrial average fell 40.49 points, or 0.32 percent, to 12,455.66. The S&P 500 Index lost 4.32 points, or 0.33 percent, to 1,314.54. The Nasdaq Composite dropped 19.68 points, or 0.69 percent, to 2,830.44.
Trading was expected to be volatile throughout the day as investors remained concerned about Greece's possible exit from the euro zone. At least half of euro zone governments as well as banks and large companies are making contingency plans in case Greece decides to leave the single currency area, even though the preferred option is still for Athens to keep the euro.
Hewlett-Packard shares rose 2 percent to $21.50 a day after the company announced plans to lay off about 8 percent of its workforce over the next couple of years.
The transport sector edged up despite a rebound in oil prices, led by gains in airlines after JPMorgan raised its price target on several carriers.
U.S. airways jumped 9.4 percent to $12.03, its highest since November 2010, and an index of airline stocks gained 2.2 percent.
After the closing bell on Wednesday, electronic trader Knight Capital Group said it suffered a pre-tax loss of $30 million to $35 million on the botched Nasdaq trading debut of social media giant Facebook and is demanding the exchange compensate that amount.
Knight Capital Group shares were down 0.4 percent at $12.39 and Facebook shares added 1.1 percent to $32.35