A file refuses to delete because something has it open, and Windows will not say what. Process Explorer from Sysinternals answers that question by listing the handles and DLLs each process holds. Version 17.2 is 3.6 MB and free. The installer is fetched from the official Sysinternals server, download.sysinternals.com.
First steps after downloading version 17.2
Start by looking at the layout, which has two sub-windows. The top one always lists the active processes along with the names of the accounts that own them.
The bottom window changes with the mode. In handle mode it shows the handles opened by the process you selected above. In DLL mode it shows the DLLs and memory-mapped files that process has loaded.
Pick a process, switch modes and compare what appears. That short routine covers most of what the tool does.
Searching for the owner of a handle or DLL
The search function answers the question of which program has a given file or directory open. It shows quickly which processes have a particular handle opened or a particular DLL loaded.
Two typical jobs are tracking down DLL-version problems and finding handle leaks. It also gives a view into how Windows and its applications work, which suits anyone curious about process internals.
When Autoruns or PowerToys fit better
Process Explorer is a diagnostic viewer, filed under PC optimization with tags such as task-manager and system-monitoring. It does not include any cleaning or tweaking functions.
For junk cleanup, alternatives include BleachBit, Glary Utilities and Advanced SystemCare. For startup entries, Autoruns is the option, and O&O ShutUp10 and PowerToys cover other Windows adjustments.
What's new in 17.2
Version 17.2 was released and updated on October 15, 2026.
Process Explorer pros and cons
Pros
- Shows the handles and DLLs opened or loaded by each process
- Search finds which process holds a given handle or DLL
- Free
- Small download at 3.6 MB
- Published by Sysinternals and served from download.sysinternals.com
Cons
- Proprietary licence, so the source is not open
- Limited visual preview of the interface
- Aimed at diagnostics, with no cleanup features described
Is Process Explorer safe?
The file is served by the publisher's own server, download.sysinternals.com, and not by TopDown APK. Sysinternals develops the tool, and it is released under a proprietary license. Before running it, confirm that the address you downloaded from matches that host.
How to install Process Explorer
- Press the download button to get the official file.
- Run the installer you saved and confirm the Windows security prompt if the publisher matches.
- Follow the setup steps, then start Process Explorer from the Start menu.
