Fix USBSTOR.SYS Errors

Sometimes Windows system displays error messages regarding corrupted or missing USBSTOR.SYS files. Situations like that can occur, for example, during a software installation process. Each software program requires certain resources, libraries, and source data to work properly. Corrupted or nonexistent USBSTOR.SYS file can therefore effect in failed execution of the started process.

USBSTOR.SYS file USB Mass Storage Class Driver. The file was developed by for use with software. Here you will find detailed information about the file and instructions how to proceed in the event of USBSTOR.SYS related errors on your device. You can also download USBSTOR.SYS file compatible with Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Vista, Windows Vista, Windows Vista devices which will (most probably) allow you to solve the problem.

Compatible with: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Vista, Windows Vista, Windows Vista

User popularity

3.1 Scanning for malicious software
3.2 System and driver update
3.3 System File Checker tool
3.4 System recovery

4 Download USBSTOR.SYS

4.1 List of USBSTOR.SYS file versions

File info

General information
Filename	USBSTOR.SYS
File extension	SYS
Description	USB Mass Storage Class Driver

Software
Program	Microsoft® Windows® Operating System
Author	Microsoft Corporation

Details
MIME type	application/octet-stream
File type	Dynamic link library
System	Windows NT 32-bit
Copyrights	© Microsoft Corporation. All rights reserved.
Character set	Unicode
Language cod	English (U.S.)

Most common USBSTOR.SYS file related problems

There are various types of errors related to USBSTOR.SYS file. USBSTOR.SYS file may be located in wrong file directory on your device, may not be present in the system, or may be infected with malicious software and therefore not work correctly. Below is a list of most common error messages related to USBSTOR.SYS file. If you encounter one listed below (or similar), please consider the following suggestions.

USBSTOR.SYS is corrupted
USBSTOR.SYS cannot be located
Runtime Error - USBSTOR.SYS
USBSTOR.SYS file error
USBSTOR.SYS file cannot be loaded. Module was not found
cannot register USBSTOR.SYS file:
USBSTOR.SYS file could not be loaded
USBSTOR.SYS file doesn't exist

USBSTOR.SYS

Application could not be started because USBSTOR.SYS file is missing. Reinstall the application to solve the problem.

Problems related to USBSTOR.SYS can be addressed in various ways. Some methods are meant only for advanced users. If you don't have confidence in your skills, we suggest consulting a specialist. Fixing USBSTOR.SYS file errors should be approached with utmost caution for any mistakes can result in unstable or unproperly working system. If you have the necassary skills, please proceed.

How to fix USBSTOR.SYS errors in just few steps?

Remember, before taking any action related to system files perform a backup copy of your data!

USBSTOR.SYS file errors can be caused by various factors, so its is beneficial to try to fix them using various methods.

Step 1: Scan your computer for any malicious software

Windows files are commonly attacked by malicious software that prevents them from working properly. First step in addressing problems with USBSTOR.SYS file or any other Windows system files should be scanning the system for malicious software using an antivirus tool.

If by any chance you don't have any antivirus software installed on your system yet, you should do it immediately. Unprotected system is not only a source of file errors, but, more importantly, makes your system vulnerable to many dangers. If you don't know which antivirus tool to choose, consult this Wikipedia article – comparison of antivirus software.

Step 2: Update your system and drivers.

Installing relevant Microsoft Windows patches and updates may solve your problems related to USBSTOR.SYS file. Use dedicated Windows tool to perform the update.

Go to the Windows "Start" menu
Type "Windows Update" in the search field
Choose the appropriate software program (name may vary depending on your system version)
Check if your system is up to date. If any unapplied updates are listed, install them immediately.
After the update has been done,restart your computer in order to complete the process.

Beside updating the system, it is recommended that you install latest device drivers, as drivers can influence proper working of USBSTOR.SYS or other system files. In order to do so, go to your computer or device producer's website where you will find information regarding latest driver updates.

Step 3: Use System File Checker (SFC) tool

System File Checker is a Microsoft Windows tool. As the name suggests, the tool is used for identyfing and addressing system file related errors, including those related to USBSTOR.SYS file. After an error related to%fileextension% file has been discovered, the program attempts to automatically replace the USBSTOR.SYS file with properly working version. To use the tool:

Go to the Windows "Start" menu
Type "cmd" in the search field
Locate "Command Prompt" result – don't run it yet:
Click the right mouse button and select "Run as Administrator" option
Type "sfc /scannow" in console prompt to start the program and follow the instructions

Step 4: Restoring Windows system

Another approach is to restore system to previous state, before the USBSTOR.SYS file error occured. In order to restore your system, follow the instructions below

Go to the Windows "Start" menu
Type "System Restore" in the search field
Start the system restore tool – it's name may differ depending on version of the system
The application will guide you through the process – read the messages carefully
After the process has finished, restart your computer.

If all the above-mentioned methods failed and the USBSTOR.SYS file problem has not been resolved, proceed to the next step. Remember that the following steps are intended only for advanced users.

Download and replace USBSTOR.SYS file

The last solution is to manually download and replace USBSTOR.SYS file in appropriate folder on the disk. Select file version compatible with your operating system and click the "Download" button. Next, go to your web browser's "Downloaded" folder and copy the downloaded USBSTOR.SYS file.

Go to the folder where the file should be located and paste the downloaded file. Below is the list of USBSTOR.SYS file example directory paths.

Windows 10: C:\Windows\System32\drivers\
Windows 8.1: C:\Windows\System32\drivers\
Windows 8: 1: C:\Windows\System32\drivers\
Windows 7: ---
Windows Vista: ---
Windows Vista: ---
Windows Vista: ---

If the steps did not solve your USBSTOR.SYS file problem, you should consult a professional. A probability exists that the error(s) might be device-related and therefore should be resolved at the hardware level. A fresh operating system installation might be necessary – a faulty system installation process can result in data loss.

File versions list

Filename USBSTOR.SYS

System Windows 10

File size 107936 bytes

Date 2017-03-18

Download

File details
	MD5	c71532ed28cfec78b7c1240858f74b16
	SHA1	ba267cf3a1baef5bc0c79146e2b3e11353903bcf
	SHA256	5d45111f558c5d1923dd29181bc2bdff1fd4f47dc2f576c31c46b38793fae07e
	CRC32	36a2b7dd
	Example file location	C:\Windows\System32\drivers\

Filename USBSTOR.SYS

System Windows 8.1

File size 120640 bytes

Date 2014-11-21

Download

File details
	MD5	b4a53fa9af30243cc7edfac75a029624
	SHA1	3e2238aedf22ba2029e0f5169e1a3731f8640012
	SHA256	8c1649b94bd7744c5b59802ce02df52a1d6bd261c23179bea76cc38318c0c564
	CRC32	f836468a
	Example file location	C:\Windows\System32\drivers\

Filename USBSTOR.SYS

System Windows 8

File size 97008 bytes

Date 2012-07-26

Download

File details
	MD5	727ce341df7efdc94f2868393549f497
	SHA1	d953768a9776e481e69871b0f9a16074b4d3ac86
	SHA256	7e2f2af92561514f4c78c5d4f825f2e9f942a66fae450aa1ea6922cbd10cc0a6
	CRC32	3d7d3e9b
	Example file location	1: C:\Windows\System32\drivers\

Filename USBSTOR.SYS

System Windows 7

File size 91648 bytes

Date 2010-11-21

Download

File details
	MD5	d76510cfa0fc09023077f22c2f979d86
	SHA1	30dcdb1d45bf0fa06d5ba254b49e2d92ba9e65aa
	SHA256	5662281c6d515423255d3c262ea368dbafc250235e535fbfa3e59d3487695439
	CRC32	66f403e1
	Example file location	---

Filename USBSTOR.SYS

System Windows Vista

File size 66048 bytes

Date -0001-11-30

Download

File details
	MD5	586d9876a4945779c8eea926c0d16889
	SHA1	21ac57557d1f970733ed389110bdd7680fe0f6e9
	SHA256	7534e7d9665942ca7663e6e5f5f1607752f9e09dd67d036da5c520e9c11e53e2
	CRC32	73fdfcfe
	Example file location	---

Filename USBSTOR.SYS

System Windows Vista

File size 77824 bytes

Date 2009-04-11

Download

File details
	MD5	b854c1558fca0c269a38663e8b59b581
	SHA1	a3669b77dfb976840bf798959dbdcaf13f8e73f9
	SHA256	08cc36b33fa2281fc88671be051863aa8ca911446d24596049db77fb4cb09ea6
	CRC32	80bc6028
	Example file location	---

Filename USBSTOR.SYS

System Windows Vista

File size 64512 bytes

Date -0001-11-30

Download

File details
	MD5	f269e18f5a5b2f69038e0af2d2cd9466
	SHA1	e38400447ce8a00108e4144f2b1765f97b32c20e
	SHA256	67652061f3d43c7040ee51dde081a8dfdd8f973273c8b8f5c73de618972f894b
	CRC32	0af39bc7
	Example file location	---