The trojan recieved notoriety after Siam Alam made a video about this trojan. It had later had a better version called MrsMajor2.exe which was featured in Siam Alam's video too.
MrsMajor, also known as BossDaMajor is a trojan for Microsoft Windows. It originates from Turkey and it was created in 2017.
Strangely enough, even though the virus itself is called MrsMajor, the executeable is called bossdamajor.exe.
After the user runs the virus, it opens Windows Media Player and restarts the system. The wallpaper is then changed to skulls and the icons are changed to skulls, too. Once the OS has fully loaded up, a a flashing and moving image of a creepy doll called "Mrs. Major" pops up on-screen. A song from League of Legends, Thresh's Theme, plays after the image appears.
A version 2.0 of the virus exists and includes rules. One of the rules tells users to not use Task Manager to end the virus. If the user attempts to open Task Manager, then a message stating "There is no escape" appears instead. If the user breaks the rules, there will be a RSoD (Red Screen of Death) screen telling the user they broke the rules of the virus. The error code is "TROJANS_NEVER_JOKE_RESPECT_THE_TROJANS", which may be telling the user that this piece of malware is a Trojan. If the user shuts down their PC while the virus is running, the virus will trash the operating system by deleting some boot files.