Nokia's share price crumbled more than 10% after it announced its latest line of smartphones.
The Finnish mobile phone company unveiled the Lumia 920 and 820 upgrades to its flagship line of devices, including new features such as wireless charging and improved cameras, at a press conference in New York.
But within an hour shares in the company had fallen by 12% on the New York Stock Exchange.
By 5pm UK time they had rallied slightly, down 9.8%.
Investors appeared to be unimpressed by the company's announcements, with most retaining deep worries about the company's ability to withstand the financial pressures suffered since losing its place at the top table of phone makers.
Apple's iPhone and latterly Google's Android ecosystem have stolen the lead from Nokia in the past six years, and according to analysts the company has failed to make up for lost ground with enough speed.
In July it said it had lost $1bn in three months, even as the number of Lumia phones it sold globally more than doubled.
Compared to 2011 its net sales in the last quarter were down 19% while operating losses grew from €287m to €826m.
And with Apple preparing to make its own major announcement on 12 September - widely expected to be an all-new iPhone 5 - the pressure will be on for Nokia to demonstrate early that users are switching in enough numbers to its devices, and the Windows Phone 8 operating system which powers them.
But Tony Cripps, principal analyst at Ovum, said that the new devices were impressive, and suggested they might have enough to help turn the company around.
"Nokia's decision to unveil its second generation Lumia devices in the US is extremely significant for the Finnish handset manufacturer, which has always struggled to make an impact in the country, even before the advent of Apple's iPhone," he said.
Others pointed to a steady rise in Nokia's share price before the announcement, which indicated it may have been overvalued.
The company's stock surged 96% from July 18 to August 17, the steepest rise for more than 20 years.
Its shares hit €2.68 earlier this week - well above the average prediction of €1.99.
"You often get a trading rally in Nokia when there is a new product,” Lee Simpson, an analyst at Jefferies Group Inc. in London, told Bloomberg last month.
"The pattern is often you buy into the expectation, but try and avoid on delivery. We said OK, you can trade into this, but beyond Sept. 5, be careful."
David McQueen, Principal Analyst at Informa Telecoms & Media, was also bullish on Nokia's chances to turn its fortunes around.
He said: "Nokia could well find itself in prime position to capitalise on the upsurge in interest. Indeed, with this latest solid array of quality smartphone products and differentiated services, the company may have finally bottomed out in the smartphone market and its WP8 devices look set to mark the true beginnings of its climb back into the affections of the smartphone user."
Nokia 920 and 820
The new Lumia 920 is Nokia's all-new, high-end device. It features a 4.5-inch curved glass display, 1.5GHz Qualcomm Snapdragon S4 dual core processor, an 8.7-megapixel camera, wireless charging and will run Microsoft's new Windows Phone 8 operating system.
Nokia said that the 920 will have a "better than HD resolution" with its PureMotion HD+ screen technology built-in.
Claiming that the screen was its "best smartphone display innovation" in its history, Nokia said it helps "keeps moving content sharp and flicker-free".
"The effect is a bright colourful display that you could even see in the desert," said Nokia's Jo Harlow.
Nokia also announced the mid-range Lumia 820, which it said "delivers high-end performance in a compact package".
The 820 has a similar look and feel to the 920, with exchangeable shells to allow users to customise their phones.
It has a 4.3-inch 800x480 screen, the same 1.5-ghz Snapdragon S4 processor as the 920 and an 8mp camera. With the use of a specially designed cover, the phone will also feature the same wireless charging capability as the 920.