OAB file icon

OAB File Extension

Offline Address Book

What is OAB file?

OAB filename suffix is mostly used for Offline Address Book files. Files with OAB extension may be used by programs distributed for Windows platform. Files with OAB extension are categorized as Data Files files. The Data Files subset comprises 1326 various file formats. The most popular program for handling OAB files is Microsoft Outlook, but users can choose among 1 different programs that support this file format. Microsoft Outlook software was developed by Microsoft Corporation, and on its official website you may find more information about OAB files or the Microsoft Outlook software program.

Programs which support OAB file extension

The following listing features OAB-compatible programs. Files with OAB extension, just like any other file formats, can be found on any operating system. The files in question may be transferred to other devices, be it mobile or stationary, yet not all systems may be capable of properly handling such files.

Programs that support OAB file

How to open file with OAB extension?

There can be multiple causes why you have problems with opening OAB files on given system. What is important, all common issues related to files with OAB extension can be resolved by the users themselves. The process is quick and doesn’t involve an IT expert. The list below will guide you through the process of addressing the encountered problem.

Step 1. Get the Microsoft Outlook

Install software to open OAB file Problems with opening and working with OAB files are most probably having to do with no proper software compatible with OAB files being present on your machine. This one is an easy one. Select Microsoft Outlook or one of the recommended programs (for example, Microsoft Office) and download it from appropriate source and install on your system. Above you will find a complete listing of programs that support OAB files, classified according to system platforms for which they are available. The safest method of downloading Microsoft Outlook installed is by going to developer’s website (Microsoft Corporation) and downloading the software using provided links.

Step 2. Check the version of Microsoft Outlook and update if needed

Update software that support file extension OABIf you already have Microsoft Outlook installed on your systems and OAB files are still not opened properly, check if you have the latest version of the software. Sometimes software developers introduce new formats in place of that already supports along with newer versions of their applications. This can be one of the causes why OAB files are not compatible with Microsoft Outlook. The most recent version of Microsoft Outlook is backward compatible and can handle file formats supported by older versions of the software.

Step 3. Associate Offline Address Book files with Microsoft Outlook

After installing Microsoft Outlook (the most recent version) make sure that it is set as the default application to open OAB files. The method is quite simple and varies little across operating systems.

Associate software with OAB file on Windows

Change the default application in Windows

  • Right-click the OAB file and choose Open with option
  • Select Choose another app → More apps
  • Finally select Look for another app on this PC, point to the folder where Microsoft Outlook is installed, check the Always use this app to open OAB files box and conform your selection by clicking OK button
Associate software with OAB file on Mac

Change the default application in Mac OS

  • By clicking right mouse button on the selected OAB file open the file menu and choose Information
  • Proceed to the Open with section. If its closed, click the title to access available options
  • From the list choose the appropriate program and confirm by clicking Change for all....
  • A message window should appear informing that This change will be applied to all files with OAB extension. By clicking Continue you confirm your selection.

Step 4. Verify that the OAB is not faulty

If you followed the instructions form the previous steps yet the issue is still not solved, you should verify the OAB file in question. Problems with opening the file may arise due to various reasons.

Check OAB file for viruses
1. Verify that the OAB in question is not infected with a computer virus

Should it happed that the OAB is infected with a virus, this may be that cause that prevents you from accessing it. Immediately scan the file using an antivirus tool or scan the whole system to ensure the whole system is safe. If the OAB file is indeed infected follow the instructions below.

2. Verify that the OAB file’s structure is intact

If you obtained the problematic OAB file from a third party, ask them to supply you with another copy. The file might have been copied erroneously and the data lost integrity, which precludes from accessing the file. If the OAB file has been downloaded from the internet only partially, try to redownload it.

3. Ensure that you have appropriate access rights

Some files require elevated access rights to open them. Log out of your current account and log in to an account with sufficient access privileges. Then open the Offline Address Book file.

4. Verify that your device fulfills the requirements to be able to open Microsoft Outlook

If the system is under havy load, it may not be able to handle the program that you use to open files with OAB extension. In this case close the other applications.

5. Check if you have the latest updates to the operating system and drivers

Latest versions of programs and drivers may help you solve problems with Offline Address Book files and ensure security of your device and operating system. It is possible that one of the available system or driver updates may solve the problems with OAB files affecting older versions of given software.

Do you want to help?

If you have additional information about the OAB file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on OAB file.

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