Upbeat earnings lifted the markets to a higher open with the Dow rising 43 points to 13,924. Nasdaq gained 15 points to 3146.

On the upside

Hewlett-Packard (NYSE: HPQ) reported lower first quarter revenue and earnings but the results surpassed analyst expectations prompting upgrades.

American International Group (NYSE: AIG) fell to fourth quarter loss due to Hurricane Sandy but the insurer's operating income beat expectations.

Aruba Networks (Nasdaq: ARUN) reversed year ago losses to post a better than expected profit for the second quarter.

On the downside

EnteroMedics (Nasdaq: ETRM) priced its public offering of 13.77 million common shares and warrants to purchase 5.508 million common shares at the discounted price of $0.95 per unit.

Volcano (Nasdaq: VOLC) disappointed with sharply lower fourth quarter earnings prompting a downgrade.

Abercrombie & Fitch (NYSE: ANF) reported higher fourth quarter earnings but same store sale fell.

In the broad market, advancing issues outpaced decliners by a margin of nearly 5 to 2 on both the NYSE and on Nasdaq. The broader S&P 500 index rose 5 points to 1507.