OAB File Extension
Offline Address Book
Overview – Offline Address Book OAB
OAB file, short for Offline Address Book, is associated with Microsoft Exchange Server accounts. OAB file stores clients' names, email-addresses, and office location which can be found in Global Address List (GAL) of Exchange Server.
As the name suggests (Offline Address Book), clients can access the OAB file's address list when connection to the MS Exchange is not available i.e. in offline mode.
OAB files needn't to be backed up as the file created & updated by the server automatically. MS Outlook in cached mode updates OAB file every 24 hours.
Application Category
Data File (Address Book)
Organization
Microsoft Corporation
MIME Type
application/octet-stream
Applications Supported
Versions
OAB Version 2 & 3
Supported by Exchange Server 2003, 2007, 2010 and MS Outlook 2003, 2007, 2010.
OAB Version 4
Supported by Exchange Server 2003, 2007, 2010, 2013, 2016 and MS Outlook 2003, 2007, 2010, 2013, 2016.
Types of OAB File
Multiple files having oab file extension are created which vary according to OAB versions:
OAB Version 2 & 3:
- Browse file: Browse.oab / Ubrowse.oab
- RDN Index file: Rdndex.oab / Urdndex.oab
- ANR Index file: Anrdex.oab / Uanrdex.oab
- Details file: Details.oab / Udetails.oab
- Display template files: Tmplts.oab / Utmplts.oab
- Changes file: Pdndex.oab / Updndex.oab
OAB Version 4:
- Full Details file
- Differential Patch file
- Display template file
Location of OAB File
Windows Vista/ 7/ 8/ 10:
\Users\user\AppData\Local\Microsoft\Outlook
Windows XP/Server 2003:
drive:\Documents and Settings\user\Local Settings\Application Data\Microsoft\Outlook
How to open and View OAB File
OAB file cannot be imported and open within outlook as an individual file. The user requires a Tool to open .oab extensions and view its details. A Freeware is an easily available option to view these files.