Sharp revenue declines and an $850 million accounting loss for goodwill impairment swung Juniper to a net loss for the fourth quarter, the company reported on Tuesday. Adjusted profits for the quarter were better than expected though, sending stock prices up in after-hours trading.

The non-cash goodwill loss stemmed from the underperformance of Juniper's security business unit, with the company determining that the unit's fair value is substantially less than that previously recorded on the balance sheet. Company officials stressed that the goodwill charge was an accounting adjustment that had no impact on cash flow or business outlook.

Without the accounting loss, Juniper would have recorded $80.4 million in net income for the quarter ended in December, or 41 cents per share, beating the consensus expectation of 31 cents, according to Reuters. Net revenue for the quarter was down 14 percent year-over-year.

"I'm not pleased or satisfied with the performance of our security business," Juniper CEO Rami Rahim said on a call with investors. "I think we can do better."

Rahim stepped up as CEO in November, following the surprise departure of Shaygan Kheradpir. The leadership turmoil, as well as a decision last summer to sell off the Junos Pulse mobile security unit for $250 million, come amid rising pressure on Juniper from activist investor Elliot Management, which has pushed for restructuring and shareholder dividends.

"We are focusing on areas where we can compete effectively," Rahim said on the investor call, describing recent losses as part of a "pivoting strategy" that would allow the company to "return to growth and investment in the second half of this year."

Whether Rahim succeeds in leading the pivot remains an open question. By quickly promoting the 17-year Juniper veteran to CEO, the company avoided a protracted leadership search, TBR Senior Analyst Scott Dennehy observed in an investor note on the results Tuesday.

"However," wrote Dennehy, "it remains to be seen if Rahim has the leadership skills to successfully navigate Juniper through its current financial challenges as well as the potentially disruptive impact NFV and SDN could have on the company’s core business over the long term."

Juniper stock rose as much as five percent in after-hours trading Tuesday.