Updated from March 2.

Seagate Technology ( STX) will deliver third-quarter earnings at the low end of its previous guidance, the hard-drive maker said after the close Tuesday.

The main culprit was slower-than-expected January sales, the company said.

Shares of Seagate, which took a $4 hit in January when the company missed its second-quarter forecast, were recently up 5 cents, or 0.3%, to $16.78.

In January, Seagate told investors to expect March quarter earnings to range from 20 cents to 30 cents a share, but the company did not give top-line guidance.

Tuesday's call had news that could indicate that demand for drives in notebooks and some business systems is slowing. But some analysts thought the slowdown noted by Seagate was a company-specific issue and not a general trouble indicator.

The company said it expects the total available market for its most important business -- personal storage, including desktops -- to decline by 5 million to 6 million units during the quarter, in line with its previous forecast. In the last quarter, personal storage accounted for more than 78% of the units shipped by Seagate.

But the total available market for enterprise storage products will be about 5 million units, 10% below the January estimate. Also, the market for mobile storage products, an important new business for Seagate, will drop 10% to 15% below the previous quarter, Seagate now believes.

In a call with analysts, Chief Executive Steve Luczo said he did not believe the company had lost market share in the quarter, and the company said pricing in the volatile industry was stable.

Analyst Ashok Kumar of Piper Jaffray said it was unclear if the issue was a "secular headwind" or an indication of Seagate's weakness and left his in-line rating on the company unchanged. (Piper Jaffray does not have a current banking relationship with Seagate.)

"Although Seagate's quarterly update will cause estimates to come down again, it is more notable in that it is bound to unleash concerns about the current health of the notebook and enterprise server and storage markets," said Laura Conigliaro of Goldman Sachs. "Our view is that we would not be too quick to judge the health of the overall industry based on Seagate's comments and conclusions." (Goldman has an investment banking relationship with Seagate.)

Still, the issue is a concern. Investors may get some clarity on the health of the computer market when leading chipmaker Intel ( INTC) delivers its midquarter update on Thursday.

Seagate disappointed investors in January when it missed its second-quarter forecasts. Instead of the 45 cents expected in the second quarter by analysts polled by Thomson First Call, the company earned 41 cents a diluted share, or $205 million, on sales of $1.76 billion, in the quarter ended Jan. 2. Gross margins slipped to 26.2% from 26.9%