Fix pacer.sys Errors

Sometimes Windows system displays error messages regarding corrupted or missing pacer.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 pacer.sys file can therefore effect in failed execution of the started process.

pacer.sys file QoS Packet Scheduler. 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 pacer.sys related errors on your device. You can also download pacer.sys file compatible with Windows 10, Windows 8.1, Windows 8, Windows 7, 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

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 pacer.sys

4.1 List of pacer.sys file versions

File info

General information
Filename	pacer.sys
File extension	SYS
Description	QoS Packet Scheduler

Software
Program	Microsoft® Windows® Operating System
Author	Microsoft Corporation

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

Most common pacer.sys file related problems

There are various types of errors related to pacer.sys file. pacer.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 pacer.sys file. If you encounter one listed below (or similar), please consider the following suggestions.

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

pacer.sys

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

Problems related to pacer.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 pacer.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 pacer.sys errors in just few steps?

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

pacer.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 pacer.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 pacer.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 pacer.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 pacer.sys file. After an error related to%fileextension% file has been discovered, the program attempts to automatically replace the pacer.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 pacer.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 pacer.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 pacer.sys file

The last solution is to manually download and replace pacer.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 pacer.sys file.

Go to the folder where the file should be located and paste the downloaded file. Below is the list of pacer.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: C:\Windows\System32\drivers\
Windows Vista: C:\Windows\System32\drivers\

If the steps did not solve your pacer.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 pacer.sys

System Windows 10

File size 129952 bytes

Date 2017-03-18

Download

File details
	MD5	36a72a16bc04efa5c29f0ac08cd5025f
	SHA1	d8a442258da6d0ac63e0fbe99cd7f946ba060a20
	SHA256	9fe6774b524a68ae429e5f9d462f6dab1cc957ae374f71ee3e3f515cb6ef8303
	CRC32	12249371
	Example file location	C:\Windows\System32\drivers\

Filename pacer.sys

System Windows 8.1

File size 122368 bytes

Date 2014-11-21

Download

File details
	MD5	96acad85693456b11d1a4e4f70ec3d4d
	SHA1	19267952a46108ae2e9013b6218ec1d59fbd8ddf
	SHA256	6b663f32deee04b878400202591d5c8d2cb900df191f8b2b1181e4e8303cf115
	CRC32	ee13f487
	Example file location	C:\Windows\System32\drivers\

Filename pacer.sys

System Windows 8

File size 131584 bytes

Date 2012-07-26

Download

File details
	MD5	42e46dc7767f5ab664e3f6b36d9764ad
	SHA1	b809f55db38c61f3306a095bcecfe88f6d3399ef
	SHA256	e4d6d493dc0c7a3881572bb238744af8b040d40c9a4a53f2a5067fbae63dc21c
	CRC32	7860ff8b
	Example file location	1: C:\Windows\System32\drivers\

Filename pacer.sys

System Windows 7

File size 131584 bytes

Date 2010-11-21

Download

File details
	MD5	0557cf5a2556bd58e26384169d72438d
	SHA1	4a26222f16ded36a2abd8b1ffc59b0114a52f1c3
	SHA256	f6f83a616b1f1c6c0df6d2ec2513e6c23fd4faa6d36518b8676c619ab74957b4
	CRC32	d62406d5
	Example file location	C:\Windows\System32\drivers\

Filename pacer.sys

System Windows Vista

File size 94208 bytes

Date 2009-04-11

Download

File details
	MD5	c5ab7f0809392d0da027f4a2a81bfa31
	SHA1	e5098ca306d851c21b8ba9aa0412fa196714b23c
	SHA256	b5bc9712ad93661a77af4d67db5f05c58a93cf7cdd6f7ba20568c0a9f4630321
	CRC32	bcb34a57
	Example file location	C:\Windows\System32\drivers\