You can view a .sys file with a text editor, but what you see depends on what the file contains
A .sys file is a system driver — a piece of code that tells Windows how to talk to hardware like your printer, graphics card, or network adapter. Most .sys files are binary, which means they contain machine code that looks like gibberish when you open them in a regular text editor. Some .sys files are text-based and readable. The tool you use depends on what you're trying to do: read the file's contents, check its properties, or troubleshoot a driver problem.
If you just want to see what's inside, a text editor like Notepad will open any .sys file, but you'll see mostly unreadable characters if the file is binary. If you want useful information about the driver — its version, what hardware it controls, or whether it's signed by Microsoft — you need a different approach. Windows itself provides built-in tools that show you driver details without opening the raw file.
Key Takeaways
- Most .sys files are binary and unreadable in a text editor, but Notepad will still open them if you need to try.
- Device Manager shows you what drivers are installed and lets you check their version, manufacturer, and status without opening the file itself.
- The System Information tool (msinfo32) displays driver details and file locations for hardware on your computer.
- If a .sys file won't load or is causing problems, Windows Event Viewer logs the error messages that explain why.
Using Notepad or another text editor
Notepad is the simplest way to open a .sys file, and it works on any Windows computer without installing anything. Right-click the .sys file, select "Open with," and choose Notepad. If the file is text-based — which is rare but possible — you'll see readable content. Most of the time you'll see random characters and symbols because the file contains compiled machine code, not human-readable text.
Other text editors like Notepad++, Visual Studio Code, or WordPad will also open .sys files. These editors don't add any special features for .sys files, but they may display the unreadable content in a way that's easier on your eyes. None of these tools will harm the file just by opening it — reading doesn't change anything. If you're looking for specific text within a .sys file, a text editor with a search function (like Notepad++ or VS Code) lets you search for keywords, though you're unlikely to find anything useful in a binary file.
Checking driver details in Device Manager
Device Manager is the Windows tool built specifically to show you information about drivers. Press Windows key + X and select Device Manager, or search for "Device Manager" in the Start menu. Find the hardware category you're interested in — for example, "Display adapters" for your graphics card or "Network adapters" for your internet connection. Right-click the device and select "Properties."
The Properties window shows you the driver's version number, the manufacturer, the date it was released, and the file location on your hard drive. Click the "Driver" tab to see the driver provider, date, and version. If you need to know the exact .sys file name and where it's stored, this is where you'll find it. You can also use this window to update, disable, or roll back a driver without ever opening the .sys file itself.
Finding driver information in System Information
System Information (msinfo32) is another built-in Windows tool that lists all drivers and their details. Press Windows key + R, type "msinfo32," and press Enter. In the left panel, expand "Components" and then select "Device Drivers." The right panel shows a list of every driver on your system, including the .sys file name, version, manufacturer, and file path.
This view is useful if you want to search for a specific driver or see all drivers at once. You can also export this information to a text file for record-keeping or troubleshooting. Unlike Device Manager, System Information doesn't let you change driver settings, but it gives you a complete inventory of what's installed.
Checking driver problems in Event Viewer
If a .sys file is causing problems — your computer crashes, a device stops working, or you see error messages — Event Viewer logs what went wrong. Press Windows key + R, type "eventvwr.msc," and press Enter. Navigate to "Windows Logs" and select "System." Look for entries marked "Error" or "Warning" that mention the driver name or the hardware it controls.
The error message in Event Viewer often tells you exactly what the problem is: the driver failed to load, it's incompatible with your Windows version, it's not digitally signed, or the hardware it controls isn't responding. These messages are much more useful than opening the .sys file itself. If you find an error, you can search for the error code online or use it to decide whether to update, reinstall, or disable the driver.
Using third-party driver tools
Programs like DriverView (from Nirsoft) or GPU-Z (for graphics drivers) display detailed information about installed drivers in a user-friendly format. These tools read the .sys files and extract information like version, date, and digital signature status without requiring you to open the raw file. They're optional — Windows tools do the same job — but some people find them easier to use.
Be cautious with driver-update software that promises to automatically update all your drivers. Many of these programs are unreliable or bundle unwanted software. Windows Update handles most driver updates automatically, and Device Manager lets you update drivers one at a time when you need to. If you use a third-party tool, stick to well-known ones like Nirsoft's utilities or GPU manufacturer tools like NVIDIA GeForce Experience.
When you actually need to look at a .sys file
In most cases, you don't need to open a .sys file at all. If a driver is working, you don't need to see its contents. If a driver is broken, Windows tools like Device Manager and Event Viewer tell you what's wrong and how to fix it. The only reasons to actually open a .sys file are curiosity, security research, or if a support technician specifically asks you to check something inside it.
If you're troubleshooting a driver problem, start with Device Manager and Event Viewer. If a device isn't working, check Device Manager for errors or unknown devices. If your computer crashes, check Event Viewer for driver-related errors. These approaches solve the problem without needing to view the .sys file itself. Opening the file in Notepad is a last resort and rarely provides useful information.
Frequently Asked Questions
Can I edit a .sys file to fix a driver problem?
No. .sys files are system files protected by Windows, and editing them will either fail or break your system. If a driver is broken, uninstall it through Device Manager and reinstall it, or roll back to an earlier version. Never try to edit the file directly.
What does it mean if I see a .sys file I don't recognize?
Open Device Manager and search for the hardware that uses that driver. If you can't find it, search the file name online along with "Windows driver." If it's a legitimate driver from a known manufacturer, it's safe. If you're unsure, ask in a tech support forum or run a malware scan.
Is it safe to delete a .sys file?
No. Deleting a .sys file will disable the hardware it controls or cause Windows to fail to start. If a driver is causing problems, disable it in Device Manager or uninstall it — don't delete the file. Windows will reinstall it automatically if needed.
Why does my .sys file show as "not digitally signed"?
Unsigned drivers are older or from manufacturers that don't sign their code. Windows will still load them, but unsigned drivers are a security risk because they could be modified by malware. Update to a signed version if one is available, or contact the manufacturer for a newer driver.
Can I view a .sys file on a Mac or Linux computer?
Yes, you can open it in a text editor, but it will look like gibberish because it's Windows machine code. The file won't work on Mac or Linux — it's specific to Windows. You need a Windows computer to use or troubleshoot a .sys file.