VBA & Macro Problems

Fix Microsoft Access Crashing After Adding a VBA DLL Declaration

Huma Ashraf Ch Oct 12, 2026 868 views

Question details

The user's application crashes after manually declaring an external DLL function in VBA.

How to Fix Microsoft Access Crashing After a VBA DLL Declaration

Product: Microsoft Access
Device & OS: not provided
Scenario: Adding and calling external DLL functions, such as DllG.dll, within an Access VBA module.
Observed behavior: Microsoft Access crashes unexpectedly when executing the VBA code containing the external API declaration.

Before you start

Before proceeding, ensure you have a backup of your Access database and verify that you have access to the official documentation for the external DLL you are trying to call.

Solution 1Recommended

Review and Correct the VBA Declare Statement

Verify that your VBA declaration exactly matches the external API's required data types, calling conventions, and parameters to prevent memory corruption and crashes.

A common cause of Access crashing when calling an external DLL is a mismatch in the API definition. External libraries like DllG.dll are not native Access system files, meaning VBA relies entirely on your manual declaration to allocate memory correctly. If parameters are incorrect, it causes an immediate fatal error.

Open the VBA Editor

Open your Microsoft Access database and press Alt + F11 to launch the Visual Basic for Applications (VBA) Editor.

Consult the API Documentation

Check the official documentation provided by the developer of the DLL (e.g., DllG.dll). Identify the exact data types required for each parameter and the expected return type.

Update the Declare Statement

Modify your Declare statement in the VBA module to match the required parameters. Ensure you are passing arguments ByVal or ByRef as specified by the API.

Compile the Database

In the VBA Editor menu, go to Debug > Compile Database to check for syntax or type mismatch errors before running the code.

External Libraries: DllG.dll is an external API library. When requesting technical support for these types of crashes, always provide both the API documentation and your exact VBA Declare statement.

Solution 2

Ensure 32-bit and 64-bit Compatibility

Office bitness heavily impacts DLL declarations. Incorrectly mapping 32-bit declarations in a 64-bit Access environment often leads to instant application crashes.

Free Microsoft Office alternative

Experience a Stable and Lightweight Office Suite with WPS Office

Tired of dealing with complex crashes and heavy system requirements in Microsoft Office? While WPS Office doesn't directly replicate Access databases, it provides a highly stable, lightweight, and free alternative for all your document, spreadsheet, and presentation needs. Enjoy seamless compatibility, powerful data handling in WPS Spreadsheets, and a familiar interface without the frustration.

1. Download the Installer: Visit the official WPS Office website and download the free installation package for your operating system.
2. Install WPS Office: Run the installer and follow the quick on-screen instructions to set up the lightweight suite.
3. Open Your Files: Launch WPS Office and directly open your existing Word, Excel, and PowerPoint files without formatting loss.

Free and lightweight office suite with minimal system requirements.Highly compatible with Microsoft Office formats including DOCX, XLSX, and PPTX.Familiar tabbed user interface ensures a smooth and easy transition.Robust spreadsheet tools with excellent formula and macro support.

microsoft office alternative - wps office

Frequently Asked Questions

Why does Microsoft Access crash immediately when executing my VBA code?

This typically occurs due to a mismatch between the expected parameters of an external DLL and what your VBA code provides, or by running a 32-bit API declaration in a 64-bit version of Access without proper adjustments.

What is DllG.dll and why is it causing an error?

DllG.dll is not a standard Microsoft Access system file. It is a third-party or custom external API library. If it causes crashes, you must review its specific documentation to ensure your VBA declaration perfectly matches its requirements.

How do I safely declare a Windows API in 64-bit Access?

In 64-bit Microsoft Access, you must include the 'PtrSafe' keyword in your 'Declare' statement and use the 'LongPtr' data type for any variables that store memory pointers or handles.

Excel & Data Problems