General Motors Co has hired Chris Liddell, the chief financial officer of Microsoft Corp , as its new finance chief, bringing in a well-regarded auto outsider who could succeed GM's acting CEO Ed Whitacre when he steps aside.

The move, announced on Monday, is the highest-profile hire for GM since it exited bankruptcy in July and completes a whirlwind reshuffling of the top U.S. automaker's senior leadership team under Whitacre this month.

At the end of November, Microsoft said Liddell would be leaving the software maker and was looking at opportunities that will expand his career beyond being a CFO, leading many to expect he would soon be named CEO of another company.

GM has been operating since July with a new board vetted by the Obama administration and, since the start of December, under acting CEO Whitacre, who had spent a career at telecommunications provider AT&T and was already GM's chairman.

Over the past three weeks, Whitacre has shaken up GM's top management ranks by promoting two executives, reassigning two others, and bringing in GM director and investment banker Steve Girsky as his adviser.

GM has begun a search for a permanent CEO although Whitacre has told directors he is prepared to see the automaker through the next stage of its restructuring and possibly through June when it is due to pay off $6.7 billion in U.S. government loans.

As CFO, Liddell will face the challenge of readying GM for a stock offering to reduce the U.S. government's 60 percent stake in the company, and winning back investor trust after accounting missteps, mounting losses, a costly bankruptcy and $50 billion in government aid.

Being CFO at Microsoft will seem like a breeze compared to what he has to do at GM, said Toan Tran, a Morningstar analyst who has followed Microsoft for several years.

It's hard to be a bad CFO at Microsoft. You don't have to deal with much when the company generates a billon dollars (in profit) a month.

GM will be a much bigger challenge, said Tran.

Liddell, 51, a New Zealand native, joined Microsoft in 2005 from International Paper Co , where he was also CFO.

At Microsoft, Liddell was a key player in a range of initiatives that reflected the company's transition to a slower growth business.

Those included Microsoft's first debt offering, a failed bid to acquire Yahoo Inc , and a cost-cutting plan set in motion last January that included the biggest job cuts the company had ever seen.

Former GM Chief Executive Fritz Henderson, who had been CFO, was dismissed by the automaker's board earlier this month. His successor as CFO, Ray Young, was reassigned to GM's international operations in Shanghai earlier this month as part of the shake-up announced by Whitacre.

IPO IN FOCUS

Whitacre had cautioned that federal pay restrictions were complicating GM's search for outside hires for key executive positions, but said last week that the company had found a replacement for Young.

Liddell earned just over $3.5 million at Microsoft last fiscal year -- about $1.1 million in salary and bonus and about $2.4 million in stock awards.

GM did not immediately detail his compensation.

One of the first challenges for Liddell will be to oversee the process of preparing post-bankruptcy accounting statements for GM that revalue its assets and liabilities.

Completing that fresh start accounting is a prerequisite for an initial public offering of GM shares.

GM has lost $88 billion since 2005, excluding results for this year that included its bankruptcy.

Steve Rattner, the former investment banker who headed the White House-appointed autos task force, said in October that he and other U.S. officials were surprised by the stunningly poor management at GM, especially in its finance operations.

Last January GM settled a five-year probe of its accounting practices by the Securities and Exchange Commission related to errors in its treatment of pensions, derivatives and precious metals.

Since emerging from bankruptcy, GM has also had a harder than expected time disposing of the smaller and money-losing brands it no longer wants, including Saturn, Saab and Hummer.

A deal to sell Saturn to Penske Automotive Group

collapsed in September.

Last week GM said it had been unable to find a buyer for Sweden-based Saab and would shut it down, but indicated this week that it could consider additional offers for the 60-year-old auto brand.

(Additional reporting by Bernie Woodall; Editing by Matthew Lewis, John Wallace and Phil Berlowitz)