What is PenClass?

PenClass.sys is a Windows driver. A driver is a small software program that allows your computer to communicate with hardware or connected devices. This means that a driver has direct access to the internals of the operating system, hardware etc. The free file information forum can help you determine if PenClass.sys is a Windows system file or if it belongs to an application that you can trust.

Run a free scan to check for PenClass drivers in need of updating

PenClass.sys file information

The process known as Pen Class Driver belongs to software Wacom Pen Class Driver by Wacom Technology (

Description: PenClass.sys is not essential for the Windows OS and causes relatively few problems. PenClass.sys is located in the C:\Windows\System32\drivers folder. The file size on Windows 10/8/7/XP is 8,138 bytes. 
The driver can be started or stopped from Services in the Control Panel or by other programs. The program has no visible window. There is no detailed description of this service. PenClass.sys is not a Windows core file. PenClass.sys appears to be a compressed file. Therefore the technical security rating is 36% dangerous, however you should also read the user reviews.

Uninstalling this variant: If there are any problems with PenClass.sys, you can also uninstall Pen Tablet software via Windows Control Panel/Add or Remove Programs (Windows XP) or Programs and Features (Windows 10/8/7).

Recommended: Identify PenClass.sys related errors

Important: Some malware disguises itself as PenClass.sys, particularly when not located in the C:\Windows\System32\drivers folder. Therefore, you should check the PenClass.sys process on your PC to see if it is a threat. We recommend Security Task Manager for verifying your computer's security. This was one of the Top Download Picks of The Washington Post and PC World.


User Comments

Drive for pen of Wacom Tablet
  Macarlo   (further information)
Treiber zum Stifttablett von Wacom
wacom driver
using an old Windows XP version of Wacom tablet on Windows8.1 , installed Wacom software from supplied CD, worked for a few days, but the got into Windows8 endless loop of automatic repair (the greatest horror of Windows8). Spent whole day looking for a fix, finally found that this file PENCLASS.SYS was listed as corrupt. Found this in srttrail.txt. Search for it. Deleted the file and Windows8 started again. Absurd Microsoft endless loop oversight. Especially since they made many of the helpful features almost inaccessable. The mistake is really Microsoft's ineptitude.

Summary: Average user rating of PenClass.sys: based on 3 votes with 4 user comments. 2 users think PenClass.sys is essential for Windows or an installed application. One user thinks it's probably harmless. One user is not sure about it.

Do you have additional information? Help other users!
What do you know about PenClass.sys:
How would you rate it:
Link for more info:
Your Name:

Best practices for resolving PenClass issues

A clean and tidy computer is the key requirement for avoiding problems with PenClass. This means running a scan for malware, cleaning your hard drive using cleanmgr and sfc /scannow, uninstalling programs that you no longer need, checking for Autostart programs (using msconfig) and enabling Windows' Automatic Update. Always remember to perform periodic backups, or at least to set restore points.

Should you experience an actual problem, try to recall the last thing you did, or the last thing you installed before the problem appeared for the first time. Use the resmon command to identify the processes that are causing your problem. Even for serious problems, rather than reinstalling Windows, you are better off repairing of your installation or, for Windows 8 and later versions, executing the DISM.exe /Online /Cleanup-image /Restorehealth command. This allows you to repair the operating system without losing data.

To help you analyze the PenClass.sys process on your computer, the following programs have proven to be helpful: Security Task Manager displays all running Windows tasks, including embedded hidden processes, such as keyboard and browser monitoring or Autostart entries. A unique security risk rating indicates the likelihood of the process being potential spyware, malware or a Trojan. Malwarebytes Anti-Malware detects and removes sleeping spyware, adware, Trojans, keyloggers, malware and trackers from your hard drive.

Other processes

PenClass.sys [all]