How Access resolves Visual Basic for Applications references

  • Article
  • Applies to:
    Microsoft Office Access 2007, Microsoft Office Access 2003

Original KB number:   824255

Note

This article applies to a Microsoft Access database (.mdb) and to a Microsoft Access project (.adp). Requires expert coding, interoperability, and multiuser skills.

Summary

This article discusses the sequence of tasks that Microsoft Office Access 2007, Microsoft Office Access 2003, Microsoft Access 2002, Access 2000, or Access 97 performs to resolve the references in Microsoft Visual Basic for Applications (VBA).

More Information

Important

This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base: 322756 How to back up and restore the registry in Windows

In Access, you can view the VBA references that are currently selected by using the Visual Basic Editor. To do this, follow these steps:

  1. Start Access.

  2. Open an Access database.

  3. Press ALT+F11 to open the Visual Basic Editor.

  4. In the Visual Basic Editor window, click References on the Tools menu.

    In the References dialog box, you can see the references that are selected.

Note

When you select a reference, you can also view the information that corresponds to the file that must be loaded to use the reference.

The pertinent file may be a type library, an object library, or a control library. The pertinent file for each reference is loaded according to the information that appears in the References dialog box. However, if the file is not found, Access searches for the file in different locations on your computer.

For each VBA reference that is selected, Access performs the following tasks:

  • Access verifies whether the referenced file is already loaded.

  • Access verifies whether the RefLibPaths registry key exists if the referenced file is currently not loaded.

    If the RefLibPaths registry key exists, Access searches for a named value that has the same name as the reference. If there is a match, Access loads the reference from the path that is mentioned in the named value.

    Note

    You can manually add the RefLibPaths registry key to the registry and, then you can add the names and the locations of any add-ins or of any libraries that are under the RefLibPaths registry key. To do this, follow these steps:

    1. ClickStart, and then click Run.

    2. In the Open box, type regedit, and then click OK.

    3. In the Registry Editor window, locate the following registry key:

      Access 2007: HKEY_LOCAL_MACHINE\Software\Microsoft\Office\12.0\Access

      Access 2003: HKEY_LOCAL_MACHINE\Software\Microsoft\Office\11.0\Access

      Access 2002: HKEY_LOCAL_MACHINE\Software\Microsoft\Office\10.0\Access

      Access 2000: HKEY_LOCAL_MACHINE\Software\Microsoft\Office\9.0\Access

      Access 97: HKEY_LOCAL_MACHINE\Software\Microsoft\Office\8.0\Access

    4. Right-click the Access registry key, point to New, and then click Key.

    5. Name the newly created key RefLibPaths.

    6. Click RefLibPaths.

    7. Right-click anywhere in the right pane, and then click String value.

    8. Name the newly created String value by using the same name as the VBA reference.

    9. Right-click the String value that you created in step 8, and then click Modify.

    10. In the Edit String dialog box, type the location of the file that must be loaded to correspond to the reference in VBA.

      The registry value name must be the file name plus the extension. The location (value data) must be the path plus the file name. For example, if you set a reference to the Northwind sample database, you can add the following values:

      • Value Name: Northwind.mdb
      • Value Data: C:\Program Files\Microsoft Office\Office11\Samples\Northwind.mdb

    11. Repeat step 7 through step 10 to add the names and to add the locations of the appropriate add-ins or of the appropriate libraries as String values.

    12. On the File menu, click Exit.

  • Access uses theSearchPathAPI to search for the referenced file if the RefLibPaths registry key does not exist or does not contain a correct reference. The following searches are performed.

    Search Area Description
    Application Directory Location of Msaccess.exe.
    Current Directory Directory that you see if you click Open on the File menu.
    System Directory The System folder and the System32 folder that are located in the Windows folder or in the WINNT folder.
    WinDir The folder where the operating system files run. This is typically the Windows folder or the WINNT folder.
    PATH Environment Variable This system variable contains a list of folders that are directly accessible by the system. Microsoft Windows NT 4.0: In Control Panel, double-click System, and then click the Environment tab. The PATH variable is in the System Variables list. Microsoft Windows 2000, Microsoft Windows XP, and Microsoft Windows Server 2003: In Control Panel, double-click System, click the Advanced tab, and then click Environment Variables. The PATH is in the System Variables list. Microsoft Windows Vista: In Control Panel, open the "System and Maintenance" item. Click System, click Advanced system settings, click the Advanced tab, and then click Environment Variables. The PATH is in the System Variables list
    File Directory The folder that contains the .mdb file, the .mde file, the .adp file, or the .ade file, and any subfolders.

Note

Access does not require the RefLibPaths registry key if the file that you want to reference is located in any of the directories that are mentioned in the table.

If Access cannot find the reference, you receive the following error message when you compile the project or when you try to run a procedure:

Your Microsoft Office Access database or project contains a missing or broken reference to the file file name.
*To ensure that your database or project works properly, you must fix this reference.

Note

While the database is open, you receive the previous error message one time for each broken reference.

For example, if you open MyDatabase.mdb and MyDatabase.mdb is missing a reference to the Microsoft Calendar Control and to the Microsoft DAO library, you receive two error messages, one for each missing reference. You do not receive the error messages again unless you do not fix the references, you close the database, and then you reopen the database. If you fix the references and then you save the database, you do not receive the error messages the next time that you open the database.

The BrokenReference property

The Application object for Access has a BrokenReference property that tells you if any references are broken. To check the BrokenReference property, follow these steps:

  1. Start Access.

  2. Open an Access database.

  3. Press ALT+F11 to open the Visual Basic Editor.

  4. Press CTRL+G to open the Immediate window.

  5. In the Immediate window, type the following command, and then press ENTER:

    ?Application.BrokenReference

    Notice that the BrokenReference property for the Application object returns True if there are missing references. Otherwise, the BrokenReference property returns False.

References

For more information about references, click Microsoft Visual Basic Help on the Help menu, type References Collection in the Search for box in the Assistance pane, and then click Start searching to view the topic.

For more information about missing references, click the following article number to view the article in the Microsoft Knowledge Base:

283806 Visual Basic for Applications (VBA) functions break in a database with missing references