Toshiba 2455 S305 Satellite 2455-S305/S306 User's Guide (PDF) - Page 225

225 If Something Goes Wrong Problems when you turn on the computer 6 Save the file and refer to it when you contact the software manufacturer. Problems when you turn on the computer These problems may occur when you turn on the power. The computer will not start. Make sure you attached the AC adapter and power cable properly or installed a charged battery. Press and hold down the power button until the on/off light changes to green. If you are using the AC adapter, check that the wall outlet is working by plugging in another device, such as a lamp. The computer starts but, when you press a key, nothing happens. You probably have a software or resource conflict. To clear the condition, press Ctrl, Alt, and Del simultaneously, then select Shutdown and Restart. Clearing the condition may get the computer running, but it won't solve a resource conflict. Read the documentation that came with the conflicting device and "Resolving a hardware conflict" on page 229. The computer is not accessing the hard disk or the diskette drive. Your computer normally loads the operating system from the hard disk. If you have a hard disk problem, you will not be able to start the computer. Insert a system diskette into the diskette drive, press the left or right arrow key and choose your boot-up device. HINT: Press F12 as you power on the computer to access the menu.