Scott served under George Washington in the Braddock Expedition, a failed attempt to capture Fort Duquesne from the French. For most of 1756 and the early part of 1757, he divided his time between Fort Cumberland and Fort Washington, conducting scouting and escort missions. In April 1757, David Bell was relieved of his command as part of a general downsizing of Washington's regiment, and Scott was assigned to Captain Robert McKenzie at Fort Pearsall. In August and September, Washington sent Scott and a small scouting party on two reconnaissance missions to Fort Duquesne in preparation for an assault on that fort, but the party learned little on either mission. In November, Scott was part of the Forbes Expedition that captured the fort. He spent the latter part of the year at Fort Loudoun, where Washington promoted him to ensign.