Hewlett-Packard's chief strategy and technology officer has announced his retirement this week, becoming the latest senior executive to leave the troubled company battling to rebuild its damaged credibility.

Shane Robison, 57, will step down as of November 1 ending his 11-years service at the company. He was a vital figure responsible for the long-term strategy at one of the US' largest technology companies. His strategic role also included mergers and acquisitions as well as research and development.

"Shane has been a powerful innovator for our business groups and other corporate divisions," HP CEO Meg Whitman said in a statement. "In an effort to drive strategy, research and development closer to the company's businesses, it will not be replacing the role of chief strategy and technology officer."

Shares of the company have dropped 17 percent since August, when HP announced plans to acquire Autonomy for $12 billion, and publicly revealed it was considering a spin-off or sale of its PC business. The former California governor candidate Meg Whitman was appointed chief executive last month after Leo Apotheker was fired due to a series of mishaps, including the poor job of convincing investors that he had not seriously overpaid for the British company, Autonomy.

Robison's departure has made many shareholders uneasy, sending shockwaves through the company and media as HP tries to regain the trust of customers and partners. HP now admits that talks about spinning-off or selling its PC division were premature and is rethinking whether to go ahead with it or not. A decision should come by the end of the month.