The
Blue Screen of Death (also known as a
stop error,
BSoD,
bluescreen, or
Blue Screen of Doom) is a
colloquialismA colloquialism is an expression not used in formal speech, writing or paralinguistics. Colloquialisms are also sometimes referred to collectively as "colloquial language". Colloquialisms or colloquial language is considered to be characteristic of or only appropriate for casual, ordinary,...
used for the error screen displayed by some
operating systemAn operating system is an interface between hardware and user which is responsible for the management and coordination of activities and the sharing of the resources of the computer that acts as a host for computing applications run on the machine. As a host, one of the purposes of an operating...
s, most notably
Microsoft WindowsMicrosoft Windows is a series of software operating systems and graphical user interfaces produced by Microsoft. Microsoft first introduced an operating environment named Windows in November 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces...
, after encountering a critical system error which can cause the system to shut down to prevent irreversable damage. It serves to present information for diagnostic purposes that was collected as the operating system issued a
bug checkA bug check is when the Windows operating system halts the moment it reaches a condition where it cannot operate safely. A bug check can be deliberately caused from a kernel-mode driver with either the KeBugCheck or KeBugCheckEx function...
.
In some rare, very extreme cases, the system will literally 'dump' all of its memory causing the users files to be deleted and lost.
The
Blue Screen of Death (also known as a
stop error,
BSoD,
bluescreen, or
Blue Screen of Doom) is a
colloquialismA colloquialism is an expression not used in formal speech, writing or paralinguistics. Colloquialisms are also sometimes referred to collectively as "colloquial language". Colloquialisms or colloquial language is considered to be characteristic of or only appropriate for casual, ordinary,...
used for the error screen displayed by some
operating systemAn operating system is an interface between hardware and user which is responsible for the management and coordination of activities and the sharing of the resources of the computer that acts as a host for computing applications run on the machine. As a host, one of the purposes of an operating...
s, most notably
Microsoft WindowsMicrosoft Windows is a series of software operating systems and graphical user interfaces produced by Microsoft. Microsoft first introduced an operating environment named Windows in November 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces...
, after encountering a critical system error which can cause the system to shut down to prevent irreversable damage. It serves to present information for diagnostic purposes that was collected as the operating system issued a
bug checkA bug check is when the Windows operating system halts the moment it reaches a condition where it cannot operate safely. A bug check can be deliberately caused from a kernel-mode driver with either the KeBugCheck or KeBugCheckEx function...
.
In some rare, very extreme cases, the system will literally 'dump' all of its memory causing the users files to be deleted and lost. They are retrievable, but the process must be carried out by a trained PC technician and some can charge over £150 (approx $320) for this particular job, which can take days at a time to carry out.
According to Microsoft, bluescreens on
NT-basedWindows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was originally designed to be a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was...
Windows systems are usually caused by poorly-written
device driverIn computing, a device driver or software driver is a computer program allowing higher-level computer programs to interact with a hardware device....
s or malfunctioning hardware. In the Win9x era, incompatible
DLLDynamic-link library , or DLL, is Microsoft's implementation of the shared library concept in the Microsoft Windows and OS/2 operating systems...
s or bugs in the kernel of the operating system could also cause bluescreens. They can also be caused by physical faults such as faulty memory, power supplies, overheating of computer components, or hardware running beyond its specification limits. Bluescreens have been present in all Windows-based operating systems since
Windows 3.1In 1983 Microsoft announced the development of Windows, a graphical user interface for its own operating system , which had shipped for IBM PC and compatible computers since 1981...
; earlier,
OS/2OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
suffered the
Black Screen of DeathThe black screen of death is a colloquialism used for the black error screen displayed by some operating systems after encountering a critical system error which can cause the system to shut down to prevent damage.Examples include:...
, and early builds of
Windows VistaWindows Vista is a line of operating systems developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...
displayed the
Red Screen of DeathThe Red Screen of Death is a nickname for the error message which existed in some beta versions of Microsoft's operating system, Windows Vista. It was dropped in Beta 1 of Windows Vista for all errors except boot loader errors...
after a boot loader error.
The term "Blue Screen of Death" originated during
OS/2OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
pre-release development activities at Lattice Inc, the makers of an early Windows and OS/2 C
compilerA compiler is a computer program that transforms source code written in a computer language into another computer language...
. During porting of Lattice's other tools, developers encountered the stop screen when NULL pointers were dereferenced either in application code or when unexpectedly passed into system API calls. During reviews of progress and feedback to
IBMInternational Business Machines Corporation, abbreviated IBM, is a multinational computer technology and IT consulting corporation headquartered in Armonk, Town of North Castle, New York, United States. The company is one of the few information technology companies with a continuous history dating...
Austin, Texas, the developers described the stop screen as the Blue Screen of Death to denote the screen and the finality of the experience.
Windows NT
In Microsoft Windows NT-based operating systems, the blue screen of death (displayed in 80x50 text mode as opposed to 9x/Me's 80x25) occurs when the kernel or a driver running in kernel mode encounters an error from which it cannot recover. This is usually caused by an
illegal operationA General Protection Fault in the Intel x86 and AMD x86-64 architectures, and other unrelated architectures, is a fault which can encompass several cases where protection mechanisms within the processor architecture are violated by any of the programs that are running, whether it be the kernel or...
being performed. The only safe action the operating system can take in this situation is to
restart the computerA triple fault is a special kind of exception generated by the CPU when an exception occurs while the CPU is trying to invoke the double fault exception handler, which itself handles exceptions occurring while trying to invoke a regular exception handler....
. As a result, data may be lost, as users are not given an opportunity to save data that has not yet been saved to the hard drive.
The text on the error screen contains the code of the error along with four error-dependent values in parentheses that are there to help software engineers fix the problem that occurred. Depending on the error code, it may display the address where the problem occurred, along with the driver which is loaded at that address. Under Windows NT and 2000, the second and third sections of the screen may contain information on all loaded drivers and a stack dump, respectively. The driver information is in three columns; the first lists the base address of the driver, the second lists the driver's creation date (as a Unix timestamp), and the third lists the name of the driver.
By default, Windows creates a memory dump file when a blue screen error occurs. Depending on the OS version, there may be several formats this can be saved in, ranging from a 64kB "minidump" to a "complete dump" which is effectively a copy of the entire contents of physical
RAM-Ram, ram, or RAM as a non-acronymic word:As a non-acronymic word Ram, ram, or RAM may refer to:-Animals:*Bighorn Sheep, A North American mountain sheep species*Sheep, an uncastrated male of which is called a ram...
. The resulting memory dump file may be debugged later, using a kernel
debuggerA debugger is a computer program that is used to test and debug other programs . The code to be examined might alternatively be running on an instruction set simulator , a technique that allows great power in its ability to halt when specific conditions are encountered but which will typically be...
. A debugger is necessary to obtain a
stackIn computer science, a call stack is a stack data structure that stores information about the active subroutines of a computer program. This kind of stack is also known as an execution stack, control stack, function stack, or run-time stack, and is often shortened to just "the stack"...
trace, and may be required to ascertain the true cause of the problem; as the information on-screen is limited and thus possibly misleading, it may hide the true source of the error.
Microsoft Windows can also be configured to send live debugging information to a kernel debugger running on a separate
computerA computer is a machine that manipulates data according to a set of instructions.Although mechanical examples of computers have existed through much of recorded human history, the first electronic computers were developed in the mid-20th century . These were the size of a large room, consuming as...
. Windows XP also allows for kernel debugging from the machine that is running the OS. If a blue screen error is encountered while a live kernel debugger is attached to the system, Windows will halt execution and cause the debugger to break in, rather than displaying the BSoD. The debugger can then be used to examine the contents of memory and determine the source of the problem.
A BSoD can also be caused by a critical boot loader error, where the operating system is unable to access the boot partition due to incorrect storage drivers, a damaged file system or similar problems. In such cases, there is no memory dump saved. Since the system is unable to boot from the hard drive in this situation, correction of the problem often requires booting from the Microsoft Windows CD. After booting to the CD, it may be possible to correct the problem by performing a repair install or by using the
Recovery ConsoleThe Recovery Console is a feature of the Windows 2000, Windows XP and Windows Server 2003 operating systems. It provides the means for administrators to perform a limited range of tasks using a command line interface...
(with
CHKDSKCHKDSK is a command on computers running DOS, OS/2 and Microsoft Windows operating systems that displays the file system integrity status of hard disks and floppy disk and can fix logical file system errors...
, or
fixboot).
ReactOS
ReactOSReactOS is a computer operating system intended to be binary compatible with application software and device drivers made for Microsoft Windows NT versions 5.x and up...
, an attempt at creating a
free softwareFree software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with minimal restrictions only to ensure that further recipients can also...
/
open sourceOpen source is an approach to the design, development, and distribution of software, offering practical accessibility to a software's source code. Some consider open source as one of various possible design approaches, while others consider it a critical strategic element of their operations...
implementation of a Windows NT-compatible
operating systemAn operating system is an interface between hardware and user which is responsible for the management and coordination of activities and the sharing of the resources of the computer that acts as a host for computing applications run on the machine. As a host, one of the purposes of an operating...
, also features its own BSoD similar to the Windows NT/XP one.
Windows 9x/Me
Perhaps the most famous instance of a Windows 9x BSoD occurred during a presentation of a Windows 98 beta by
Bill GatesWilliam Henry "Bill" Gates III is an American business magnate, philanthropist, and chairman of Microsoft, the software company he founded with Paul Allen.He is ranked consistently one of the world's wealthiest people...
at
COMDEXCOMDEX was a computer expo held in Las Vegas, Nevada, each November from 1979 to 2003. It was one of the largest computer trade shows in the world, usually second only to the German CeBIT, and by many accounts one of the largest trade shows in any industry sector...
on April 20, 1998. The demo PC crashed with a BSoD when his assistant (Chris Capossela, who is still working for Microsoft as Corporate VP in the Information Working business unit) connected a scanner to the PC, trying to demonstrate Windows 98's support for Plug and Play devices. This event brought thunderous applause from the crowd and Gates replied after a nervous pause:
"That must be why we're not shipping Windows 98 yet."
Windows CE
The simplest version of the blue screen occurs in
Windows CEWindows CE is an operating system developed by Microsoft for minimalistic computers and embedded systems. Windows CE is a distinctly different operating system and kernel, rather than a trimmed-down version of desktop Windows...
except the versions for
Pocket PCA Pocket PC, abbreviated P/PC or PPC, is also known by Microsoft as a 'Windows Mobile Classic device'. It is a hardware specification for a handheld-sized computer that runs the Microsoft 'Windows Mobile Classic' operating system. It may have the capability to run an alternative operating system...
, which appears similar to the ones found in Windows NT/2K/XP.
Windows 1.0
The very first Blue Screen of Death happens in
Windows 1.0Windows 1.0 is a 16-bit graphical operating environment that was released on 20 November 1985. It was Microsoft's first attempt to implement a multi-tasking graphical user interface-based operating environment on the PC platform. Windows 1.0 was the very first version of Windows launched...
if a computer fails to boot up properly, it will show random letters and symbols.
If Windows 1.0 encounters any (
MS-DOSMS-DOS is an operating system developed by Microsoft. It was the most commonly used member of the DOS family of operating systems and was the main operating system for personal computers during the 1980s. It was preceded by M-DOS , designed and copyrighted by Microsoft in 1979...
related) critical system errors, it will instead show a
Black Screen of DeathThe black screen of death is a colloquialism used for the black error screen displayed by some operating systems after encountering a critical system error which can cause the system to shut down to prevent damage.Examples include:...
.
See also
- Sad Mac
A Sad Mac is an iconic symbol used by older-generation Apple Macintosh computers , starting with the original 128K Macintosh, to indicate a severe hardware or software problem that prevented startup from occurring successfully. The Sad Mac icon was displayed, along with a set of hexadecimal codes...
—An Apple equivalent to the BSoD, found in both early Macs and iPodiPod is a brand of portable media players designed and marketed by Apple and launched on . The product line-up includes the hard drive-based iPod Classic, the touchscreen iPod Touch, the video-capable iPod Nano, and the compact iPod Shuffle. The iPhone can function as an iPod but is generally...
s.
- Kernel panic
A kernel panic is an action taken by an operating system upon detecting an internal fatal error from which it cannot safely recover. The term is largely specific to Unix and Unix-like systems; for Microsoft Windows operating systems the equivalent term is "Stop error" .The kernel routines that...
—A critical failure under UnixUnix is a computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
and Unix-likeA Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification....
operating systems.
- Linux kernel oops
An oops is a deviation from correct behavior of the Linux kernel which produces a certain error log. The better-known kernel panic condition results from many kinds of oops, but others may allow continued operation with compromised reliability...
- Guru Meditation
Guru Meditation is the name of the error that occurred on early versions of the Commodore Amiga computer when they crashed. It is analogous to the "Blue Screen Of Death" in Microsoft Windows operating systems...
—A type of error message for AmigaThe Amiga was a family of personal computers originally developed by Amiga Corporation. Development on the Amiga began in 1982 with Jay Miner as the principal hardware designer. Commodore International bought Amiga Corporation and introduced the machine to the market in 1985...
operating systems.
- Screens of death on video game consoles
- Red Ring of Death—A red warning light/symbol on the Xbox 360 that means an inoperative unit.