The following are the processor exceptions and their definitions:
00: Divide Fault
The 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 interrupt
Interrupt 2 is reserved for the hardware Non-Maskable-Interrupt condition.
No exceptions trap through interrupt 2.
04: Overflow trap
The overflow trap occurs after an INTO instruction has executed and the 0F
bit is set to 1.
05: Bounds Check Fault
The 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 fault
This error is returned if any one of the following conditions are true:
- The processor tries to decode a bit pattern that does not correspond to any legal computer instruction
- The processor attempts to execute an instruction that contains invalid operands
- The processor attempts to execute a protected-mode instruction while running in virtual 8086 mode.
- The processor tries to execute a LOCK prefix with an instruction that cannot be locked.
07: Coprocessor not available fault
This 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 Fault
Processing 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 Overrun
This 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 Fault
Because the Task State Segment contains a number of descriptors, any number
of conditions may cause exception 0A. Typically, the processor can gather
enough information from the Task State Segment to issue another fault
pointing to the actual problem.
11 (0Bh): Not Present Fault
The 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 Fault
A 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 Fault
Any condition which 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 application.
- ... Error while initializing IOS when starting Win95 — usually caused by SMARTDRV.EXE — delete it!
- ... While initializing NTKERN: Windows Protection Error when starting Win95 — is usually caused by Windows — install updated amdk6upd.exe if you have an AMD processor
- ... at 0xxx:bff7xxxx This is NOT related VIDEO memory, or video drivers. It is a problem in KERNEL32.DLL... but not necessarily with Windows.
14 (0Eh): Page Fault
The Page Fault interrupt allows the operating system to implement virtual
memory on a demand-paged basis. An interrupt 14 usually is issued whenever
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.
- ... occurred at 0028:C000xxxx in VxD VMM (01) + 0000xxxx — usually caused by graphics card driver
16 (10h): Coprocessor error Fault
This interrupt occurs when an unmasked floating-point exception has been
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 Fault
This is only used on the 80486 [or better] CPUs. It occurs when code 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.
This document appears to be quite old, since it does not refer to
Pentium processors. Taken from Microsoft's Knowledge Base, Q150314.