By Tom Hals

WILMINGTON, Delaware (Reuters) - A letter that had prompted Mark Hurd's abrupt resignation as chief of Hewlett-Packard Co was ordered unsealed by a Delaware judge, potentially revealing more details of his dramatic exit last year.

The letter was sent to Hurd from Gloria Allred, a high-profile California lawyer, on behalf of an independent contractor who had accused him of sexual harassment. It prompted the world's top computer maker to investigate Hurd, who has since joined Oracle Corp as president.

Although HP's board found no evidence of sexual harassment, Hurd, 53, stepped down on August 6 after the company accused him of filing inaccurate expense reports involving Jodie Fisher, the contractor.

Delaware Chancery Judge Donald Parsons wrote in an opinion issued late Thursday that much of the information was already public and he determined the contents of the letter were not protected.

"We are disappointed with the court's ruling," said Hurd's lawyer, Amy Wintersheimer. "We believe the letter, which was clearly marked 'confidential,' should remain that way."

Parsons ordered the letter to be made public in 10 days. However, Hurd's lawyer said her client intends to appeal, which will likely delay the order to lift the seal.

The 71-page opinion disclosed some of the letter's details, noting that Hurd was accused of using corporate funds to "wine and dine" Fisher and leaked to her "potentially material" nonpublic information about the company.

"While some of the allegations in the letter concerning Hurd's conduct vis-a-vis Fisher are candid, they are not graphic or lurid," wrote Parsons. "Unsealing the letter would not publicly reveal entirely new information about Hurd; instead, it simply would provide more details concerning a matter of established public knowledge."

Parsons did write that the letter contains some "intimate details" about Hurd's private life and his relationship with his family.

The judge specifically cited portions of the letter that would remain under seal. For example, the order read "On page seven, first full paragraph: redact the entire rest of the paragraph following the first sentence ending with 'a married man'."

Hurd and Fisher have said the letter contains "many inaccuracies."

The dispute over the letter stems from a lawsuit by a shareholder, Ernesto Espinoza, who is seeking HP's records relating to Hurd's resignation and severance package. The company agreed the letter was not confidential, but Hurd intervened in the case to fight to keep it from the public.

Fisher has said the letter contained "many inaccuracies."

Espinoza's lawyers did not return a call for comment.

The case is Ernesto Espinoza v Hewlett Packard Co, Delaware Chancery Court, No. 6000.

(Reporting by Tom Hals, editing by Gerald E. McCormick, Dave Zimmerman)