Netflix (NFLX) stocks tumbled on Tuesday after news that the company had lost over 800,000 subscribers, many of whom were angered by an abortive attempt by the company to split its streaming and mail-delivery video services. 

Netflix shares plunged 35 percent Tuesday after the one-time Wall Street favorite revealed a massive departure of subscribers angered by price increases and other questionable changes at rental service that was created to make entertainment a snap.

Netflix revealed late Monday that it ended September with 23.8 million U.S. subscribers. That’s down about 800,000 from June and worse than what the company had hinted at before. In September, the company predicted it will lose about 600,000 U.S. customers.

And it may get worse. Netflix said it expects more defections in coming months.

The exodus began after the company raised its prices by as much as 60 percent in July and split up its streaming and DVD rental services. Its website was flooded by comments from angry customers. Many people also canceled service, especially on the DVD-by-mail side. The company is betting that its future is in streaming video, and CEO Reed Hastings has said he expects Netflix’s DVD subscriptions to steadily decline, much like what has happened to AOL Inc.’s dial-up Internet service.

But Netflix bungled a spin off its DVD-by-mail service, giving it the name Qwikster and creating separate accounts for people who wanted both DVDs and movie streaming. By doing so, the company created what many perceived to be a more complicated rental process at a company that began its meteoric rise with a new, easier way of searching for and finding entertainment effortlessly.

Netflix shares tumbled $41.34 to $77.50 in late morning trading Tuesday. The stock is down from more than $300 just 3 ½ months ago. The last time the stock was trading so low was in April 2010, but that was during an extraordinarily steep ascent, after the company nearly erased the omnipresent blue and yellow storefronts of Blockbuster.

After what critics said was the poor execution of the attempted split and the resulting fallout, Netflix CEO Reed Hasting was quick to try to reassure investors the core business model was strong. As Cliff Edwards explained :

Investors are trying to gauge the extent of the fallout from the price increase and aborted plan to put DVD customers on a new service called Qwikster.

“To show even modest U.S. subscriber growth in the fourth quarter will require significant ramp-up in Netflix’s marketing spending,” said Paul T. Sweeney, director of research for Bloomberg Industries.

Hastings downplayed the likelihood of a big increase in marketing efforts.

“Our streaming marketing has been very effective in the past two years,” Hastings said. “We are going to work on improving the user interface, expanding to more platforms and delivering more content. There’s no grand gestures, there’s just a lot of steady and intense efforts.”

Domestic streaming subscriptions are forecast to decline this month, level off in November and rebound in December to end at 20 million to 21.5 million, Netflix said. DVD subscriptions will fall “sharply” to 10.3 million to 11.3 million customers.

Fourth-Quarter Outlook

Fourth-quarter profit will be $19 million to $37 million, or 36 cents to 70 cents a share, on revenue of as much as $875 million, the company said. Analysts were projecting profit of $1.10 a share on sales of $919 million, according to Bloomberg data. The company earned $47.1 million, or 87 cents a share, on sales of $595.9 million, a year earlier.

Domestic subscriber growth is particularly important because Netflix has used its wide lead over U.S. rivals to finance growth in its streaming business and expand overseas.

Netflix had projected a loss of 600,000 users on Sept. 15 to end the third quarter at 24 million. The actual results were in line with the average loss of 780,000 customers seen by 10 analysts in a Bloomberg survey.

Domestic churn, a measure of subscriber turnover, jumped to 6.3 percent in the third quarter from 4.2 percent in the prior three months. The company’s total subscriber count, including service in Canada and Latin America, fell to 25.3 million from 25.6 million