Access Database

How Do I Fix MS Access Unrecognized Database Format Error

Microsoft Access users commonly experience the ‘Unrecognized database format’ error. This error may appear due to several reasons. Let’s check the causes of the ‘unrecognized database format .accdb error and the plausible solutions.

Cause 1: Inadequate permissions to access the database

Upgrading Windows Server, say from Windows 2003 to Windows 2008 R2, involves a number of steps viz. removal of the old ownership and permission, saving all the files on external HDD, creating new owners, assigning permissions to new owners, and providing full access and more.

But even after performing these steps diligently, only the domain administrator may open the Microsoft Access database. But when the other users try to open the Access DB file on the same server, they get an error message – “Access Unrecognized Database Format, database is corrupt or in an inconsistent state”.


  • In case if the domain admin with full access rights can open the Access database on the server, the issues is due to permissions on the domain or that folder where the Access database is located. Granting full permissions to all users on the network share may help resolve the “Unrecognized Database Format Access, the database is corrupt or in an inconsistent state”.
  • If the issue is still not resolved, assign Local Admin rights to all the users on that server.
  • Lastly, check the custom permissions on the database which displays the Access unrecognized database format error. 

As a primary check, the domain administrator should ensure the following with regard to the users accessing the Access database:

  1. The users are logged into that domain where Access database is located
  2. The users have local and custom admin rights to access the database, as required

Cause 2: Using Access 2016 along with Visual Studio 2012

A similar error can be displayed when a user tries to access Microsoft Access 2016 database while working on Visual Studio 2012. The sequence of events involves:

  1. User selects the Database source type and the Dataset database model.
  2. The software asks for which database connection to use to connect to the database. When the user clicks “New User”, and chooses the Microsoft Access Database File (OLE DB in this case).
  3. Next, the application confirms the type of database connection to be used where the user says: “New Connection.”
  4. User clicks on “New Connection” and selects the file name – Microsoft Access Database File (OLE DB).
  5. When the filename is displayed, the user selects an appropriate file – “xyz.accdb”
  6. The user checks the connection by clicking Test Connection, which results in Microsoft Access unrecognized database format error: Unrecognized database format’ C:…..\xyz.accdb

In this case, the issue arises probably due to the difference created by the line provider or Microsoft Ace OLE DB version on the Line Provider. Thus, installing the upgraded version in the Server Explorer may help resolve the issue as in this case, Microsoft.ACE.OLEDB.4.0 is upgraded to Microsoft.ACE.OLEDB.12.0.


The error can be resolved by upgrading the application Microsoft.ACE.OLEDB.4.0 to Microsoft.ACE.OLEDB.12.0. To update, connect the Access 2016 with the help of following steps:

  • Add a new Data source and click Database, followed by Dataset.
  • Go to New Connection and click Microsoft Access Database File
  • Select ACCDB file
  • Click Advanced to change the provider’s name
  • Click OK to add connection windows and Test connection and verify.

You should have Microsoft.ACE.OLEDB.12.0 and not Microsoft.Jet.OLEDB.4.0 (as the earlier version cannot recognize database in ACCDB format) 

Cause 3: Opening the database in different versions, and abrupt closure

  1. Saving and opening Access DB file with a different version may result in incompatibility in MS Access database due to version conflict.
  2. The abrupt closure of database file or system when the database is in the process of completing a backend operation may result in Microsoft Access Unrecognized Database Format Error. The forcible closure of the Access file or the system on which the file is logged results in incomplete query resolution, which causes corruption in the Access database and the error situation.
  3. Similarly, closing the system without completing the “Access file saving” process may also result in inconsistency in Access database and displays the following error message:  “Unrecognized Database Format Access, the database is corrupt or in an inconsistent state”. The abrupt closure of Microsoft Access is more frequent when the database is stored at a shared network. Multiple users may try to access the database at the same time, and changes made by one of the users may remain unsaved due to abrupt file closure, thus resulting in corruption in the Access database.
  4. The user was using Microsoft Access database and trying to enter some values with the help of a form but was unable to enter the values through that form due to an error. The error message reads as: “Unrecognized database format S:\Folder name\Sub folder name\xyz.accdb”


Inaccessible Access database may result in corruption, which can be resolved with the help of the following:

Use Microsoft suggested auto repair option or “Compact and database Repair” utility:

  • Launch Microsoft Access and go to Database Tools
  • Select Database Utility “Compact and Repair Database” option
  • A new window opens. Select the database file which shows the error code
  • Click compact to initiate the Access database repair process

Note: Take a backup of the Access database before starting the repair process. Reason being:

  • Compact and Repair utility may not repair all the corrupt entities. During repair, Access may truncate some data, which can possibly be recovered from backup.
  • Does not repair interface objects such as forms or reports. In case the backup copy is not available, then the user may end up losing data available in forms and reports.

Limitations of compact and Repair Utility:

  • Does not repair severely damaged and extensive database
  • The drive must have enough space to store the compacted and the original database.
  • Cannot repair all components of the database.

Repair Access DB with the help of Stellar Repair for Access software

Stellar Repair for Access helps resolve Access file corruption error like “Microsoft Access Unrecognized Database Format Error”.

Free download
  • Open the software and click Browse to select the corrupted Access database file. Alternatively, click Search to find for corrupt Access database amongst the Drive, folder or sub-folder.
  • Click Option to Scan for Deleted Records to include the deleted records to save the repaired database
  • Select Repair to initiate the repair process. Once the software completes the database-repair process, it generates a Log Report of the fixed components, and displays a message “Repairing of selected database completed.”
  • Click Ok, and the software displays a preview of the Tables
  • Verify the components of a repaired database and click Save to initiate the database saving process.
  • Click Browse to specify the location of the repaired database.

The tool repairs severely corrupt large Access database and also recovers all the database components.


“Microsoft Access Unrecognized Database Format Error” may appear while upgrading the system or when a user is trying to access Microsoft Access database file through a different application like Visual Studio. The error may also be caused due to corruption in Access database, which might happen due to abrupt or improper shutdown.

With various plausible causes of the error, it is necessary to find the exact cause and resolve it with the help of the right solution.

All the causes and their resolution methods are discussed above. It’s important to consider that Repair and Compact method may not be effective in case of large and severely corrupt database files. In such cases, a specialized Access database repair software could be a more effective choice. 

The software-based resolution method also helps to recover the deleted records of Microsoft Access database.  

  1. air force one sh June 25, 2020

Leave a Reply

Your email address will not be published. Required fields are marked *

Time limit is exhausted. Please reload CAPTCHA.