WASHINGTON (AP) — As a supporter of presidential candidate Barack Obama, Cynthia Stroum was a superstar whose financial backing of the campaign landed her a plum diplomatic posting in Europe.

As America’s ambassador to Luxembourg, the wealthy Seattle-based businesswoman was a disaster.

According to an internal State Department report released Thursday, less than a week after she quit, Stroum’s management of the U.S. Embassy in the tiny country was abysmal. The report says her tenure of about one year was fraught with personality conflicts, verbal abuse and questionable expenditures on travel, wine and liquor.

Stroum’s case illustrates the pitfalls that presidents can face when they appoint non-career diplomats to ambassadorships as a reward for their political support.

The Luxembourg embassy “has underperformed for the entirety of the current ambassador’s tenure,” said the report, which was prepared last fall before she resigned abruptly. “At present, due to internal problems, it plays no significant role in policy advocacy or reporting, though developments in Luxembourg are certainly of interest to Washington clients and other U.S. missions in the NATO and EU communities.”

Stroum resigned effective Jan. 31, just days before the scathing report from the State Department’s inspector general was made public. A message left with a person who answered the phone at her Seattle home said she was unavailable for comment. The call was not returned.

In a farewell message published in the Luxembourg press, Stroum said she was leaving the job because she wanted to return to private life. “The reality is that I now need to focus on my family and personal business,” she said.

At the State Department, her departure was not announced. Spokesman Mark Toner gave no hint of problems when asked about the situation. “We are grateful for her service to the United States and wish her all the best in her new endeavors,” he said.

But the report paints a picture of a corrosive atmosphere at the small embassy, with the ambassador running roughshod over staff, threatening to read their e-mails, largely concerned about job-related perks and involved in improper purchases.

The situation was so bad that the inspector general recommended that the State Department dispatch medical personnel to Luxembourg to test the stress levels of embassy employees. It said at least four staffers quit or sought transfers to Iraq and Afghanistan during her tenure, unusual steps for diplomats assigned to a modern, Western European capital.

“The bulk of the mission’s internal problems are linked to her leadership deficiencies, the most damaging of which is an abusive management style,” the report said. “She has followed a pattern of public criticism of colleagues, including (deputies), who have not performed to her satisfaction.”

“Those who have questioned or challenged some of the ambassador’s actions state that they have paid a heavy price in the form of verbal abuse and been threatened with dismissal,” it said.

The report said the State Department was aware of the situation and that a perceived lack of action in dealing with it could be harmful. “It is unfortunate that an impression is being created among officers and local employees at this mission that this kind of behavior may be routinely tolerated by Department of State leadership, particularly for non-career ambassadors.”

Stroum began her short diplomatic career in 2009 when Obama nominated her to the cushy position of U.S. ambassador to the Grand Duchy of Luxembourg, a tiny nation of 500,000 people about the size of Rhode Island and surrounded by France, Belgium and Germany.

Aside from her business experience as an investor, entertainment producer and philanthropist active in numerous charities, Stroum’s major qualification for the post appeared to be her generous contributions to Democratic politicians and causes, particularly Obama’s campaign.

Financial reports say Stroum donated the maximum personal amount to Obama’s campaign. She also donated $2,300 to the failed presidential campaign of former Sen. John Edwards.

As a fundraiser, the records show she was responsible for ginning up at least $500,000 for Obama, putting her near the top of the campaign’s money generators.

The inspector general said it had learned in interviews with embassy staffers that Stroum, shortly after her arrival in Luxembourg, discussed with them “the importance she attaches to the perquisites of” being an ambassador. As such, she was particularly concerned about the state of the ambassador’s residence, which was being renovated, it said.

Because of the renovation, Stroum sought temporary housing. An embassy official spent six weeks searching for an appropriate property and, using contacts in Luxembourg, Belgium, Germany and France along with two officials from the U.S. Embassy in Brussels, screened 200 properties and visited 30 to 40.

They found only four that met the ambassador’s requirements and she rejected all of them, according to the report, before an acceptable residence finally was found.

Apart from those difficulties and management problems, the report identified several improprieties while Stroum was in charge in Luxembourg. Among them:

— Stroum spent $2,400 to fly with an aide to a Swiss “professional school” whose graduates have gone on to work for Buckingham Palace and similar places to interview candidates to replace a retired property caretaker and a fired chef. The purpose of the trip was listed as “management meetings.” Although no one from the school was hired, such recruitment is allowed only if there are no qualified local employees. In addition, they did not get proper authorization for the trip.

— The embassy purchased $3,400 in wine and liquor a day before the 2010 budget year ended in an effort spend as much of its annual entertainment funds as possible. The booze did not arrive until the next fiscal year and State Department rules say embassies are not allowed “to use excess year-end funds” to buy items unless they are used in that year.

— Stroum was reimbursed for the purchase of a new bed because she “preferred a queen bed to the king-size bed already provided.” The embassy twice asked Washington to reimburse the amount but was denied because it was a personal choice. Despite the refusals, the No. 2 at the embassy signed off on a voucher “reimbursing the ambassador for the cost of the mattress out of program funds.” The report said the voucher needs to be repaid.