In early 2010, an Afghan man approached the NDS claiming to represent senior Taliban commander Mullah Akhtar Muhammad Mansour. Offering a letter allegedly written by Mansour, he said Mansour was interested to open a channel for negotiations. Saleh's people started testing the credentials of the supposed messenger, and judged them to be false, closing the case. The man then approached other Afghan government institutions. Saleh recounts, "When I learned ... that he was going through a different avenue, I warned the government that if it is this Aminullah, if he claims this, and if it is this guy, trust me, he is not representing anybody; it's a scam. ... Be careful. This is not Mansour. But there was a perception that Amrullah is against talks, so let's sideline him." The Afghan man, who lived in Pakistan where the Taliban's leadership council is based, subsequently held three meetings with NATO and Afghan officials. Having been flown from Pakistan to Kabul on a NATO airplane, the man met with President Karzai in the presidential palace. In late 2010, it turned out, that the supposed representative for Mansour was an impostor as Saleh had previously warned. The New York Times writes: "In an episode that could have been lifted from a spy novel, United States and Afghan officials now say the Afghan man was an impostor."
On June 6, 2010, Saleh resigned from the NDS while Atmar resigned from his position as interior minister after a militant attack against the national peace jirga, although nobody had been killed or wounded and the attackers had been arrested. A few days after the jirga, Karzai had summoned Atmar and Saleh to discuss the attack against the jirga. After the meeting both men officially resigned because of the failure to stop the attack on the jirga. CNSNews writes: "Saleh told reporters he had submitted his resignation as general director of National Security because he had lost Karzai's trust as a result of the attack. He said he and Atmar had briefed the president on the security preparations for the jirga, and the subsequent "success in ... capturing the facilitators", but Karzai had not been satisfied. He had therefore felt unable to continue in his post. He also said there were "tens" of reasons for leaving his position, but would not elaborate on others." The two men's resignation led to widespread concerns among Afghanistan experts. Concerns were voiced over the direction the country was moving in.
It was reported in 2010 that the Inter-Services Intelligence (ISI) and the Taliban "regarded Saleh as their fiercest opponent." He subsequently founded the Basej-e Milli (National mobilization) and Green Trend as a pro-democracy and anti-Taliban movement.