For 99.9% of users today, Autoruns64a is the only relevant version. Running the plain autoruns64.exe on a standard PC will result in an immediate "This app can't run on your PC" error, because the instruction sets for Itanium and x64 are binary incompatible.
Conversely, running autoruns64a on an Itanium server would fail. However, given that Microsoft dropped support for Itanium over a decade ago, encountering such a server in the wild is extraordinarily rare.
Scenario: You have a new Snapdragon X Elite laptop. Malware hides a persistence entry via a custom ARM64 shell extension.
Recommendation: Use autoruns64a exclusively on ARM64 hosts.
Before diving into the differences between Autoruns 64 and Autoruns 64a, it's essential to understand what Autoruns is and its role in Windows system management. Autoruns is a comprehensive utility that provides detailed information about programs and services configured to start automatically on a Windows system. This includes not just the obvious startup folders and registry keys but also lesser-known locations such as drivers, Winlogon, and more.
False. Wine emulates Windows APIs on x86/x64. It does not emulate ARM64 Windows binaries. Avoid.
The distinction between autoruns64 and autoruns64a is not about features or performance, but about historical architecture. The former is a relic for a dead platform (Itanium), while the latter is the workhorse for the x64 world we live in today. This seemingly redundant pair serves as a quiet reminder of the turbulent transition to 64-bit computing. For the system administrator or power user, the lesson is simple: ignore the "64" and look for the "a" —it is the tool that will keep your modern Windows system secure and booting cleanly.
The primary difference between autoruns64.exe autoruns64a.exe processor architecture
they are designed to run on. Both are 64-bit versions of the Sysinternals Autoruns utility, but they target different hardware platforms. Microsoft Learn Core Technical Differences autoruns64.exe (x64) : This version is built for x86-64 (AMD64/Intel 64)
processors. It is the standard executable for the vast majority of modern 64-bit Windows laptops and desktops using Intel Core or AMD Ryzen chips. autoruns64a.exe (ARM64) : The "a" suffix stands for . This version is compiled specifically for
processors, such as the Qualcomm Snapdragon chips found in "Always Connected" PCs (e.g., Surface Pro 9 with 5G or Samsung Galaxy Book). Microsoft Learn Functionality Comparison
Aside from their underlying architecture, the two files offer identical features for managing startup locations: autoruns64.exe autoruns64a.exe Full Graphical User Interface (GUI) Full Graphical User Interface (GUI) 64-bit Windows (x64) 64-bit Windows (ARM64) Scans registry, services, and tasks Scans registry, services, and tasks Supports VirusTotal hash checks Supports VirusTotal hash checks Which One Should You Use?
For a standard Windows installation on an Intel or AMD processor, you should use autoruns64.exe
. If you try to run the wrong version, Windows will typically display an error stating that the file is "not a valid Win32 application". Microsoft Learn
If you prefer using the command line instead of the visual interface, look for the counterparts autorunsc64.exe autorunsc64a.exe (ARM64), where the "c" indicates the command-line version. Microsoft Learn suspicious startup items? Which autoruns executable to use? - Microsoft Q&A
Paul Jackson 26. Feb 12, 2021, 3:23 AM. Hello, The Sysinternals Autoruns utility includes multiple executable files: autoruns.exe, Microsoft Learn Which autoruns executable to use? - Microsoft Q&A
Paul Jackson 26. Feb 12, 2021, 3:23 AM. Hello, The Sysinternals Autoruns utility includes multiple executable files: autoruns.exe, Microsoft Learn Which autoruns executable to use? - Microsoft Q&A
Paul Jackson 26. Feb 12, 2021, 3:23 AM. Hello, The Sysinternals Autoruns utility includes multiple executable files: autoruns.exe, Microsoft Learn Sysinternals Utilities - Microsoft Learn
To understand why you cannot simply use one binary everywhere, let us examine the internal behavior.
