April 20, 2004
What Are Fatal Exception Errors (Q150314)
This article was previously published under Q150314
If this article does not describe the error message that you are receiving, view the following Microsoft Knowledge Base article to view more articles that describe error messages:
315854 Windows 98 and Windows Me Error Message Resource CenterTo view a list of articles applicable to Fatal Exception 0E errors in Windows 98, click to view the following link:
SUMMARYWhen you attempt to shut down your computer, start Windows, or start a program in Windows, you may encounter error messages that are similar to:
A fatal exception XY has occurred at xxxx:xxxxxxxxFatal exception errors are codes that are returned by a program in the following cases:
In the sample error message that is listed above, XY represents the actual processor exception from 00 to 0F. (Note that the "h" that is listed after the 0E, 0F, and so on, in the explanations below is frequently omitted from the error message.) The xxxx:xxxxxxxx value represents the enhanced instruction pointer to the code segment; the 32-bit address is the actual address where the exception occurred.
Windows does not cause these errors, but has the exception-handling routine for that particular processor exception, which displays the error message.
NOTE: This article is primarily for informational use. Click the following link to go to the "Troubleshooting Fatal Exception Errors" section of this article:
Processor Exceptions and Their Definitions
00: Divide FaultThe processor returns this exception when it encounters a divide fault. A divide fault occurs if division by zero is attempted or if the result of the operation does not fit in the destination operand.
02: NMI InterruptInterrupt 2 is reserved for the hardware Non-Maskable-Interrupt condition. No exceptions trap through interrupt 2.
04: Overflow TrapThe overflow trap occurs after an INTO instruction has executed and the 0F bit is set to 1.
05: Bounds Check FaultThe BOUND instruction compares the array index with an upper and lower bound. If the index is out of range, then the processor traps to interrupt 05.
06: Invalid Opcode FaultThis error is returned if any one of the following conditions exists:
07: Coprocessor Not Available FaultThis error occurs if the computer does not have a math coprocessor and the EM bit of register CR0 is set indicating that Numeric Data Processor emulation is being used. Each time a floating point operation is executed, an interrupt 07 occurs.
This error also occurs when a math coprocessor is used and a task switch is executed. Interrupt 07 tells the processor that the current state of the coprocessor needs to be saved so that it can be used by another task.
08: Double FaultProcessing an exception sometimes triggers a second exception. In the event that this occurs, the processor will issue a interrupt 08 for a double fault.
09: Coprocessor Segment OverrunThis error occurs when a floating point instruction causes a memory access that runs beyond the end of the segment. If the starting address of the floating point operand is outside the segment, then a General Protection Fault occurs (interrupt 0D).
10 (0Ah): Invalid Task State Segment FaultBecause the Task State Segment contains a number of descriptors, any number of conditions can cause exception 0A. Typically, the processor can gather enough information from the Task State Segment to issue another fault pointing to the actual problem. See Microsoft's Programming the 80386/80486 Guide for more information.
11 (0Bh): Not Present FaultThe Not present interrupt allows the operating system to implement virtual memory through the segmentation mechanism. When a segment is marked as "not present," the segment is swapped out to disk. The interrupt 0B fault is triggered when an application needs access to the segment.
12 (0Ch): Stack FaultA Stack Fault occurs with error code 0 if an instruction refers to memory beyond the limit of the stack segment. If the operating system supports expand-down segments, increasing the size of the stack should alleviate the problem. Loading the Stack Segment with invalid descriptors will result in a general protection fault.
13 (0Dh): General Protection FaultAny condition that is not covered by any of the other processor exceptions will result in a general protection fault. The exception indicates that this program has been corrupted in memory, usually resulting in immediate termination of the program.
14 (0Eh): Page FaultThe Page Fault interrupt allows the operating system to implement virtual memory on a demand-paged basis. An interrupt 14 usually is issued when an access to a page directory entry or page table with the present bit set to 0 (Not present) occurs. The operating system makes the page present (usually retrieves the page from virtual memory) and re-issues the faulting instruction, which then can access the segment. A page fault also occurs when a paging protection rule is violated (when the retrieve fails, or data retrieved is invalid, or the code that issued the fault broke the protection rule for the processor). In these cases the operating system takes over for the appropriate action.
16 (10h): Coprocessor Error FaultThis interrupt occurs when an unmasked floating-point exception has signaled a previous instruction. (Because the 80386 does not have access to the Floating Point unit, it checks the ERROR\ pin to test for this condition.) This is also triggered by a WAIT instruction if the Emulate Math Coprocessor bit at CR0 is set.
17 (11h): Alignment Check FaultThis interrupt is only used on the 80486 CPUs. An interrupt 17 is issued when code executing at ring privilege 3 attempts to access a word operand that is not on an even-address boundary, a double-word operand that is not divisible by four, or a long real or temp real whose address is not divisible by eight. Alignment checking is disabled when the CPU is first powered up and is only enabled in protected mode.
Troubleshooting Fatal Exception Errors
Clean Boot Your ComputerBecause there are many conditions that can cause a fatal exception error, the first step in resolving the issue is to narrow the focus. To narrow the focus, try a "clean boot" of your computer.
Clean-boot troubleshooting refers to methods of reducing problems that may occur because of your computer's environment. Many problems occur because of conflicting drivers, terminate-and-stay-resident programs (TSRs), and other settings that are loaded when your computer starts. For additional information about how to clean-boot your computer, click the article numbers below to view the articles in the Microsoft Knowledge Base:
192926 How to Perform Clean-Boot Troubleshooting for Windows 98
243039 How to Perform a Clean Boot in Windows 95
Query the Microsoft Knowledge BaseTo determine if the error message that you are receiving is documented in the Microsoft Knowledge Base, search the Microsoft Knowledge Base at:
242450 How to Query the Microsoft Knowledge Base Using Keywords
Articles About Fatal Exception Error MessagesFor additional information about fatal exception error messages, click the article numbers below to view the articles in the Microsoft Knowledge Base:
133440 Error Message: This Program Has Caused a Fatal Exception 0D at 00457:000040B1 and Will Be Terminated
192803 Fatal Exception 0D Using ATI All-in-Wonder Pro Video Adapter
175211 Fatal Exception Error When Opening or Closing Control Panel
171195 Fatal Exception Error Suspending and Resuming with MSDLC32
187214 Err Msg: A Fatal Exception 0E Has Occurred at 0028:C02A0201...
190123 Error Message: A Fatal Exception 06 Has Occurred at...
252523 Fatal Exception Error Message When Attempting to Connect to the Internet
189655 Err Msg: A Fatal Exception 0E Has Occurred at 0028:<XXXXXXXX>NOTE: This list of articles is not comprehensive. If one of these articles does not address your issue, use the steps in the "Query the Microsoft Knowledge Base" section of this article to find more information.
If you have any questions or problems, please feel free to contact me by Email or by phone.
© Davis M McCarn 2004 All Rights Reserved