While opening the Access database, you may encounter the “unrecognized database format” error. This error can prevent you from opening your database file. It generally occurs when Access fails to read the format of the database. Besides this, it can occur due to various other reasons. This article mentions different methods to help you fix the error.
Why Unrecognized Database Format Error Occurs in MS Access?
Several reasons could be associated with the “unrecognized database format” error in Access. Some possible causes are:
- Trying to open the Access database file of the latest version in an older version or vice-versa
- Microsoft Access application is outdated
- Bad sectors on the hard drive
- Large-sized database files
- Database file turns corrupted
- Sudden shutdown of the system
- Virus or malware attack
- Hardware or software issues
- Corrupted/damaged frxque32.mdb file
Methods to Fix the “Unrecognized Database Format” Error in MS Access
This section will discuss the methods you can easily employ to eliminate the “unrecognized database format” error in MS Access.
Method 1: Verify and Change the MS Access Database Format
The error “unrecognized database format” simply indicates that the Access application does not recognize the database format. It usually occurs when you try to open the older version (2003 or earlier) database file (mdb) in an advanced version (2010 or thereafter). To troubleshoot this, you can convert the older version file (mdb) into a newer one (accdb). Here’re the steps to do this:
- First, open your Microsoft Access application.
- Navigate to File > Open.
- Select the desired database file (older version file).
- Go to File and then click the Save As option.
- Select Save Database As option.
- Click on the Access file type and then select Save As.
- In the Save As dialog box, write a file name in the File name field and then click Save.
Method 2: Uninstall/Rollback Office Updates
Sometimes, the “unrecognized database format” error can occur if you download faulty Office updates. If the issue occurred right after installing the Office updates, you can try to roll back the downloaded updates. Reverting back to Office’s earlier version helps many users fix the error (see how to do this herer).
Method 3: Disable the Leasing
The “unrecognized database format” error can also occur while using VBA code. It usually appears when trying to open a database file (stored on a network file share) using DAO (Database Objects). Such an issue appears when multiple users use the same database. To troubleshoot this, disable the leasing on the system where the shared database is saved. Follow the steps below:
- Click on the Windows Search box and type Command Prompt.
- Right-click on Command Prompt and click Run as administrator.
- Next, copy and paste the following commands into the CMD window:
REG ADD HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters /v DisableLeasing /t REG_DWORD /d 1 /f
NET STOP SERVER
NET START SERVER
- Hit the Enter key.
- Close the Command Prompt.
Method 4: Rename the frxque32.mdb File
Sometimes, the “unrecognized database format” error can occur while launching the Queue monitor in Access. It occurs due to the corrupted frxque32.mdb file. The frxque32.mdb file is a component of FRx SysData directory. This directory contains all the necessary files for the FRx applications. You can try renaming the frzque32.mdb file to fix the issue.
Method 5: Import Data into a New MS Access Database
Corruption in the database is also one of the reasons behind the “unrecognized database format” issue. In such a case, you try importing the objects from the corrupted database into a new MS Access database. Here are the steps:
- In the Access application, double-click on the Blank Database.
- Click the File and then select Close.
- Click the Create option to create a new database.
- In a newly created database file wizard, select the External Data button.

- Click on the Import Access Database option.
- On the Get External Data-Access Database wizard, click the Browse tab and select the desired database file.
- Click on the option “Import tables, queries, forms, reports, macros, and modules into the current database” and click OK.
- On the Import Objects dialog box, select all the database objects and select OK.

Method 6: Repair your Access Database
If importing data into the new database fails to fix the error, then you can try Microsoft Access’s built-in utility – Compact and Repair. This tool compacts and repairs the oversized and corrupted database file. The tool clears unused space to reduce the database file size. Follow the below steps to use this utility:
- Open the Microsoft Access application.
- Then, double-click the Blank Database option.
- Go to File > Close.
- Click Database Tools and then select Compact and Repair Database.
- On the Database to compact from the dialog box, click on the Browse option to select the database you want to repair. Click Compact.
- Choose a location where you want to save the repaired database file and then select Save.
In some cases, Microsoft Access’ built-in tool fails to repair the database file. If this happens, try a professional MS Access database repair tool, such as Stellar Repair for Access (see StellarInfo.com). The tool can easily repair severely corrupted database files. After repairing, the tool provides an enhanced preview of all the recoverable objects with complete accuracy. To check this, you can download the software’s demo version and evaluate it for free. Once satisfied with the functionality, you can activate the tool and save the recoverable files. The tool supports MS Access 2019, 2016, and older versions.
Conclusion
The ‘unrecognized database format’ error can occur for various reasons, such as incorrect file format, corrupted frxque32.mdb file, or damaged Access file. Follow the methods mentioned above to fix the error. If the issue has occurred due to a severely corrupted database file, try a professional third-party Access repair tool like Stellar Repair for Access. It can repair the Access database file and retrieve its data with complete integrity. The tool can help you in fixing corruption-related issues without any hindrance.
Last Updated: August 31, 2023