If you are familiar with registry you can do the following alterations.. however be careful if you are completely ignorant of windows registry go for online computer support...
1. Open the registry editor on your computer. Go to the "Run" command in the "Start" menu, type "regedit" and press "Enter." Some shutdown viruses can deny you access to the registry editor. In this case, download and install an alternate registry editor and open it.
2. Make a copy of your registry, especially if you are using the computer's main registry editor. Editing anything in the registry is dangerous and can damage the computer. Go to "Start," "Programs," "Accessories," "System Tools" and "System Restore." Choose "create a Restore Point" and follow all instructions the dialogue box gives you.
3. Search the registry keys within "HKEY_CURRENT_USER." Look for autorun keys that include "shutdown," "pc off" or something similar within the data name. Delete these registry keys by right-clicking on them, selecting "Modify" and clicking "Delete."
Open your computer's "Program Files" folder. Search for EXE files that appear related to the shutdown virus--they will very likely have the same "shutdown-pc off" title. Delete these files and immediately clear your "Recycling Bin."
5. Open your "Task Manager" by inputting "taskmgr.exe" in the "Run" command. Go to the "Processes" tab and search for the processes with the same names as the deleted files. Right-click these processes and select "End Process" to kill them.