After the war, "Indiana" returned to training exercises with the North Atlantic Squadron. In May 1900, she and "Massachusetts" were placed in reserve as the navy had an acute officer shortage and needed to put the new and into commission. The battleships were reactivated the following month as an experiment in how quickly this could be achieved, but "Indiana" was placed in the reserve fleet again that winter. In March 1901, it was decided to use her that summer for a midshipman practice cruise, and this would be her regular summer job for the next few years, while the rest of the time she would serve as a training ship. She was decommissioned on 29 December 1903 to be overhauled and modernized. The obsolete battleship received several upgrades: new Babcock & Wilcox boilers, counterweights to balance her main turrets and electric traversing mechanisms for her turrets. She was recommissioned on 9 January 1906 and manned by the former crew of her sister ship "Massachusetts", including Captain Edward D. Taussig, commanding. "Massachusetts" had been decommissioned the day before to receive similar modernization.