0xC0000005

0xC0000005 is a Windows error and exception code that denotes an access violation. It is commonly referred to as STATUS_ACCESS_VIOLATION in Windows NTSTATUS values and is reported when a process attempts to access memory in a way that is not permitted, such as reading from or writing to an invalid or protected address or attempting to execute code from a non-executable region. In crash reports and debugging tools, 0xC0000005 appears as the exception code and is associated with a faulting instruction and a faulting address.

In practice, this code indicates a memory access error at the native code level. The fault can arise from dereferencing null or uninitialized pointers, use-after-free scenarios, buffer overruns or underruns, and incorrect type casts that lead to invalid reads or writes. It can also occur due to driver or kernel-mode interactions, hardware faults, or corrupted memory. In managed environments such as the .NET framework, a similar condition is represented by System.AccessViolationException, which can occur when unsafe code or interop with native libraries attempts illegal memory access.

Diagnosing 0xC0000005 typically involves collecting a crash dump or enabling a minidump and analyzing it with a debugger. Look for the faulting address, the instruction pointer at the time of the crash, the module or DLL involved, and the stack trace to identify the offending code path. Common mitigation includes code-level fixes such as proper pointer initialization, rigorous bounds checking, safe memory management patterns, and avoiding use-after-free patterns; in some cases it may require updating drivers, running memory diagnostics, or applying software patches to address underlying causes.