it was wrong to climb alone and to attempt summiting without using supplementary oxygen. This is confirmed by Sharp's emails to other climbers in which he stated he did not believe in using extra oxygen. He joined four climbers on this expedition, so Sharp relented on that point of disagreement, but only for a time, as he would return in 2006 for his solo attempt. As a result of his 2004 attempt, Sharp incurred frostbite on his fingers during the expedition. 2006 Mount Everest expedition Two years later, Sharp returned to Everest to reach the summit on a solo climb arranged through Asian Trekking. This attempt would ultimately cost him his life. Sharp was climbing alone and had intended to reach the summit without using supplementary oxygen, which is considered to be extremely risky even for very strong acclimatised mountain climbers or Sherpas. However, Sharp apparently did not consider it a challenge to climb Everest with supplementary oxygen. Sharp was climbing with a bare-bones "basic services" package from Asian Trekking that does not offer support after a certain altitude is reached on the mountain or a Sherpa to climb with as a partner, although this option was available to Sharp for an additional fee. He was grouped with 13 other independent climbers – including Vitor Negrete, Thomas Weber, and Igor Plyushkin who also died attempting to summit that year – on the International Everest Expedition. This package only provided a permit, a trip into Tibet, oxygen equipment, transportation, food, and tents up to the Mount Everest "Advance Base Camp" (ABC) at an elevation of about . The group Sharp was with was not really an expedition and had no leader, although it is considered good climbing etiquette that members of the group make some effort to keep track of one another. Before Sharp booked his trip with Asian Trekking, his friend McGuinness, an experienced climber and guide, invited him to join his organised expedition at a discount. Sharp acknowledged this as a good deal but declined so he could act independently and climb at his own pace. Critically, Sharp opted to climb alone without a Sherpa, deciding not to bring sufficient supplementary oxygen (reportedly only two bottles, which is enough for about 8 to 10 hours of climbing at high altitude) and without a radio to call for help if he encountered problems. Sharp was transported by vehicle to the