What is wab.exe, File Size, Location & How to Fix it?

Wab.exe is a part of Outlook and belongs to Windows Address Book (WAB). This is an application that lets users manage a list of contacts that can be shared by multiple applications like Microsoft Outlook. In Windows 10, wab.exe is not a process or service which runs in the background. It is just an application that opens the modified Contacts folder in which you can store contact details (E-mail, phone, address, ID) of people.

Wab.exe process information.jpg

If wab.exe is causing problems on your PC, you should follow this article in which we will discuss some details and simple ways to deal with the file.

What is wab.exe?

The full form of Wab is Windows Address Book which clearly mentions that it is used to store address or contact detail. This executable file is a part of Outlook and used to store contact detail in different format like:

  • CSV
  • LDIF
  • vCard
  • Windows Address Book File (Outlook Express contacts)

Wab.exe contact

File Size & Location

The genuine wab.exe has the following properties:

File Name:wab.exe
File Size:5046 KB
File Location:C:\Program Files\Windows Mail
Publisher:Microsoft Corporation
File Description:Windows Contacts

Usually, the wab.exe file is located under  C:\Program Files\Windows Mail but can also be located under C:\Program Files (x86)\Windows Mail in Windows 10. Whereas file size could be either 504 or 506 KB.

Is wab.exe safe or malware?

Yes, its a safe and trustworthy application. It is a Windows program file made by Microsoft Corporation and is not a background process. wab.exe is digitally signed by Microsoft and normally doesn’t causes any issues. However, if it is running in the background, it might be a trojan virus (A virus program disguised as wab.exe).

To check whether wab.exe is a virus or not, you can right-click on it and open its properties. The file should be located in C:\Program Files\Windows Mail. If it is not located there and does not have a Microsoft digital signature, it is a virus program that may cause problems in your PC.

Don’t worry, in this article, we will cover some easy methods to fix the issues.

Issues related to wab.exe

In case wab.exe is a virus, it will cause certain issues like

  • Unregistered DLL files
  • High resource usage (CPU, Disk or Memory)
  • Errors while trying to open Outlook Contacts folder
  • Slowing down your system
  • Interfere with Windows processes

In that case, we will have to remove/repair the file to bring your system to a normal working state.

Methods to repair wab.exe file

In case if the Windows Address Book is not opening at your PC then below steps can be used to fix this error:

Method 1: Re-registering WABSyncProvider.dll

High CPU usage can be caused by unregistered DLL files in the operating system registry. Follow the steps below to re-register the DLL (Dynamic-Link Library) file.

1) Press Windows+R to open the Run application

2) In the Run application, copy and paste the following code in the text field

  • regsvr32 WABSyncProvider.dll

3) The DLL will be re-registered in the OS registry.

register.dll file

4) Restart Windows.

Method 2: Using Windows Defender to scan your PC for threats

Note: If you have third-party antivirus software, you should use it to scan your PC instead of using Windows Defender.

1) Search Windows Security in the start menu and open it

2) Click on Virus & Threat Protection and press Quick scan button


Virus and threat protection quick scan

4) Wait a few minutes for the scan to finish

3) Alternatively, you can also do a full scan, but it may take some time.



Bipul is an undergraduate engineering student, who has used five different Windows releases over 8 years of him being a true PC enthusiast.