NEW YORK (CNN/Money) - Stocks headed for a cautious open Thursday, as investors found disappointment in a surprise jump in weekly jobless claims on a day of reflection on the second anniversary of the Sept. 11 terrorist attacks.

Just after 8:30 a.m. ET, futures pointed to a flat start for the major indexes.

The markets will open and close at the usual times, but activity will be halted at the NYSE at 9:59 a.m. and 10:29 a.m. ET for a minute of silence to mark the moments the World Trade Center's north and south towers fell after being struck by hijacked jetliners. The Nasdaq will also observe the moments of silence and has urged its members to refrain from trading during these times. In addition, both markets will pause for a minute at 8:46 a.m. and 9:03 a.m., before the official start of trading, to mark the times when the airplanes hit each tower.

Many market participants in New York will join in the ceremony commemorating the attack at Ground Zero, blocks away from the New York Stock Exchange.

"It will be a very subdued day for obvious reasons. People will be reflecting on what happened in the past year as well as what happened this time two years ago," Steve Previs, a dealer in U.S. stocks at Jeffries International in London, told Reuters. "A lot of people will probably just stay away from the market today."

The potential for memories of the Sept. 11 events to hurt market sentiment was illustrated Wednesday as a decline in the market widened following what was said to be a new videotape and audiotape of Osama bin Laden, the alleged mastermind of the attacks. The Dow Jones industrial average ended down 0.9 percent, at its low for the day.

Thursday, investors found disappointment in a reading on weekly jobless claims ahead of the opening bell. The number of initial claims rose to 422,000 in the week ended Aug. 31 from a revised 419,000 in the prior week. Economists had expected a drop in claims to 400,000, the key level signifying economic weakness. The reading pressured stocks after the monthly unemployment reading for August, released last Friday, showed a surprise drop in jobs when economists had expected a rise.

A report on the trade deficit showed it rising to $40.3 billion in July from a revised $40 billion in June. Still, the number came in a bit lower than economists' $40.5 billion forecast, according to Briefing.com.

Tech stocks will draw attention again after two straight losses for the Nasdaq composite index, including Wednesday's 2.7 percent drubbing that followed a disappointing forecast from chipmaker Texas Instruments.

Among the closely watched techs will be software maker Adobe Systems, which posted increased and better-than-expected fiscal third-quarter income and said current-quarter profit could top expectations on sales at the high end of forecasts. UBS raised its price target on Adobe to $42 from $36 a share following the report. Among U.S. stocks trading in Europe, Adobe (ADBE: Research, Estimates) shares jumped 5.5 percent in pre-market trading.

But shares of Microsoft (MSFT: Research, Estimates) were more than 2 percent lower as the No. 1 maker of software for PCs revealed another security flaw with its Windows operating system.

IBM (IBM: Research, Estimates) also could garner attention after Smith Barney cut its rating on the company to "underperform" from "in-line" and recommended that clients take profits in a research note dated Wednesday. The firm said it doesn't agree with some other analysts that IBM is an ideal "late-cycle play." Shares of IBM slipped nearly 1.5 percent in pre-market trading on Instinet.

Meanwhile, U.S. Bancorp Piper Jaffray raised its price target onCisco Systems (CSCO: Research, Estimates) to $22 from $19 in a research note dated Wednesday. Shares of Cisco fell 32 cents to $20.46 Wednesday.

Tokyo's Nikkei index tumbled 2.9 percent Thursday after the Wall Street losses and the purported bin Laden tape, but other Asian-Pacific markets were mixed. European stocks also were mixed at midday there. (Check the latest on world markets.)

Treasury prices fell in early trading, sending the 10-year note yield up to 4.30 percent from 4.27 percent late Wednesday. The dollar weakened slightly against the yen and euro.

Brent oil futures advanced 16 cents to $27.52 a barrel in London, where gold was above $380 an ounce in early trading.  

-- staff and wire reports