A+ Interpreting Blue Screen Stop Error Codes Quiz

Stop code 0x000000C4 (DRIVER_VERIFIER_DETECTED_VIOLATION) appears when Driver Verifier, a Windows diagnostic tool that stress-tests drivers, catches a driver doing something illegal. Technicians often enable Driver Verifier deliberately to identify a problem driver, so this crash names the culprit. Once found, the driver is updated or removed, and Driver Verifier is turned off.

Stop code 0x00000133 (DPC_WATCHDOG_VIOLATION) occurs when a driver takes too long to finish a deferred procedure call, so Windows halts to protect the system. After a new SSD install, the usual cause is outdated SSD firmware or an incompatible storage controller driver. Updating both usually resolves it. Monitor cables, time zones, and user profiles are unrelated.

Stop code 0x00000024 (NTFS_FILE_SYSTEM) occurs when Windows hits a problem reading or writing the NTFS file system, often because of bad sectors, a failing hard disk, a faulty SATA cable, or controller problems. Running chkdsk /f and checking the drive’s S.M.A.R.T. status are standard first steps. The other codes point to drivers, CPU hardware, and memory.

Because stop code 0x000000BE means a driver tried to write to read-only memory, the fix is to update or roll back the driver responsible, often one installed or updated just before the crashes began. The crash dump usually identifies it. BIOS memory settings, disk write protection, and the boot loader are not involved in this error.

With stop code 0x0000007B, start by confirming the BIOS/UEFI detects the boot drive and that the SATA mode, such as AHCI or RAID, has not changed since Windows was installed. These quick checks often fix the problem. Reinstalling Windows is a last resort, and the CMOS battery or an antivirus scan rarely addresses this error.

Stop code 0x0000000A (IRQL_NOT_LESS_OR_EQUAL) occurs when a kernel-mode driver or process tries to access memory at an interrupt request level that is too high, most often because of a faulty or incompatible device driver. Updating, rolling back, or removing the recently installed driver usually resolves it. Disk space, antivirus conflicts, and DirectX are unlikely causes.

Stop code 0x00000019 (BAD_POOL_HEADER) means the header of a memory pool, the area Windows uses to allocate memory to drivers and processes, has been corrupted. A faulty driver writing outside its allocated memory is the usual cause, though failing RAM can also contribute. It has nothing to do with network pools, partitions, or caches.

Stop code 0x000000F4 (CRITICAL_OBJECT_TERMINATION) occurs when a process Windows needs to keep running, such as csrss.exe or wininit.exe, stops unexpectedly. Because the system cannot function without it, Windows halts. Common causes include a failing storage drive, loose cables, corrupted system files, or malware. User profiles, network drops, and backup power are unrelated.

Stop code 0x0000001A (MEMORY_MANAGEMENT) indicates a serious memory management error and most often points to faulty or incompatible RAM. Running Windows Memory Diagnostic or MemTest86 and reseating or replacing modules are standard next steps. KERNEL_MODE_EXCEPTION_NOT_HANDLED usually points to drivers, DRIVER_POWER_STATE_FAILURE involves sleep transitions, and CRITICAL_OBJECT_TERMINATION means an essential system process stopped unexpectedly.

Stop code 0x0000009F (DRIVER_POWER_STATE_FAILURE) occurs when a driver fails to handle a power state change correctly, typically while the computer enters or wakes from sleep or hibernation. Network, graphics, and USB drivers are common culprits. Updating drivers or adjusting power settings usually resolves it, since the problem is software, not physical power hardware.

Stop code 0x0000007E (SYSTEM_THREAD_EXCEPTION_NOT_HANDLED) appears when a system thread throws an exception that Windows cannot handle, most often due to an incompatible, outdated, or corrupted driver. Booting into Safe Mode and updating or removing the driver usually fixes it. NTFS_FILE_SYSTEM involves the file system, INACCESSIBLE_BOOT_DEVICE the boot drive, and DRIVER_IRQL_NOT_LESS_OR_EQUAL an invalid memory access.

Stop code 0x0000003D (INTERRUPT_EXCEPTION_NOT_HANDLED) means Windows received a hardware interrupt it could not process correctly. It usually points to a faulty driver or failing hardware that is generating interrupts the system does not expect. Updating drivers and checking recently added devices are good starting points. It is not specific to CD-ROM, printer, or sound devices.

Stop code 0x0000001E (KMODE_EXCEPTION_NOT_HANDLED) means a program running in kernel mode, usually a driver, generated an error that Windows could not handle. Faulty or incompatible drivers are the most common cause, followed by hardware problems. The crash dump often names the responsible driver file. User applications run in user mode and do not trigger this code.

Stop code 0x000000EA (THREAD_STUCK_IN_DEVICE_DRIVER) occurs when a device driver gets stuck in an endless loop, usually while waiting for hardware that never responds. It is most often linked to graphics card drivers or a failing video card. Updating the display driver, checking GPU temperatures, and testing the card are typical troubleshooting steps.

Stop code 0x000000BE (ATTEMPTED_WRITE_TO_READONLY_MEMORY) occurs when a driver tries to write to memory that Windows has marked read-only, which the name itself describes. A faulty or outdated driver is the usual cause. It is generally a software problem rather than a hardware fault. PAGE_FAULT_IN_NONPAGED_AREA involves missing memory, while the power-state and Driver Verifier codes describe different driver problems.

Stop code 0x000000A5 (ACPI_BIOS_ERROR) means the system’s ACPI firmware, which handles power management and hardware configuration, is not fully compatible with Windows. It often appears during installation or after hardware changes. Updating the BIOS/UEFI firmware or resetting its settings to defaults usually resolves it. The disk controller, power supply, and CMOS battery are unrelated.

Stop code 0x0000009C (MACHINE_CHECK_EXCEPTION) is raised when the processor itself detects a fatal hardware error. Common causes include a failing CPU, faulty RAM, motherboard problems, overheating, or unstable overclocking. Troubleshooting starts with checking temperatures, removing any overclock, and testing memory. Drivers, registry corruption, and third-party software rarely trigger this error.

Stop code 0x00000050 (PAGE_FAULT_IN_NONPAGED_AREA) occurs when Windows requests data that should always be in memory but cannot find it. Faulty RAM, a bad driver, or a corrupted file system are the usual causes, so running Windows Memory Diagnostic is a good first step. The other codes point to file system, hardware, and driver-loop issues.

Stop code 0x000000D1 (DRIVER_IRQL_NOT_LESS_OR_EQUAL) occurs when a driver tries to access an invalid memory address at a raised interrupt request level. The cause is almost always a faulty, outdated, or conflicting driver, often for network or storage devices. The crash dump usually names the driver file, which tells the technician what to update.

Stop code 0x0000007B (INACCESSIBLE_BOOT_DEVICE) means Windows lost access to the system drive during startup. Common causes include a changed SATA mode in BIOS/UEFI, such as switching between AHCI and RAID, a missing storage controller driver, a loose cable, or a failing drive. It is unrelated to RAM, graphics drivers, or network adapters.