The Supercomputer Reboot Program is a program created by Franz Hopper. The only time Jeremie launched this program was in Wrong Exposure. The program refreshes all functions and inhabitants of Lyoko. The program was discovered written on a blackboard in the background of a picture of Franz Hopper and Aelita, in early form.
This program manifests itself as two waves of blue energy that sweep the sectors of Lyoko. When the first wave passes, anything it intercepts freezes and remains immobile until the second wave passes through. This program also seems to be the only way to free Aelita from X.A.N.A.'s control (short of devirtualizing her) after being possessed by the Scyphozoa. However, this process also leaves Aelita severely weakened until she enters a tower.
Linguistics
Based on the fact that the source code is mainly written in complex equations, it's probable that the program was written in Fortran, an early programming language for scientific math. Another possibility is that it was written in Haskell. According to Franz Hopper's Diary, he finished creating Lyoko in 1994, a little while after that photo was taken. At that time, Haskell was only 4 years old at most, making it unlikely, but possible, that the program was written in Haskell.