ERROR_DELAY_LOAD_FAILED - 1285 (0x505)
An attempt to delay-load a .dll or get a function address in a delay-loaded .dll failed.
Updated: Feb 21, 2026
Technical Meaning
The ERROR_DELAY_LOAD_FAILED error (1285, 0x505) indicates that an attempt to delay-load a dynamic link library (DLL) or retrieve a function address from a delay-loaded DLL has failed. Delay loading is a technique used by Windows to load the required functions of a DLL only when they are needed.
Error Details
This error typically occurs during the execution of a program where the system attempts to dynamically resolve and load functions at runtime, rather than linking them statically at compile time. The failure can be due to various reasons such as incorrect function names, missing dependencies, or issues with the DLL itself.
Usage Context
This error is commonly encountered in scenarios where dynamic linking is used, such as when a program dynamically loads additional functionality from external libraries. It may also occur during debugging or when running applications that rely on specific versions of DLLs.
Developer Interpretation
When this error occurs, it suggests that the application attempted to use functions from a delay-loaded DLL but failed to resolve them properly. This could be due to several factors including:
- Incorrect function names or signatures in the calling code.
- Missing dependencies required by the DLL.
- Issues with the DLL itself such as corruption or incorrect versioning.
Related Errors
ERROR_DELAY_LOAD_FAILEDis related to issues with dynamic linking and can be associated with other errors likeERROR_INVALID_FUNCTION, which indicates an invalid function name, orERROR_MOD_NOT_FOUND, which suggests that a required module was not found.
FAQ
Q: What does ERROR_DELAY_LOAD_FAILED mean?
A: It means the system failed to delay-load a DLL or resolve a function from a delay-loaded DLL. This can occur due to incorrect function names, missing dependencies, or issues with the DLL itself.
Q: How can I troubleshoot this error?
A: Review the calling code for correct function names and signatures. Ensure all required dependencies are present and correctly versioned. Check the integrity of the DLLs involved.
Summary
The ERROR_DELAY_LOAD_FAILED error (1285, 0x505) is a specific technical issue related to dynamic linking in Windows applications. It indicates that an attempt to delay-load a DLL or resolve a function from a delay-loaded DLL has failed due to various potential causes such as incorrect function names, missing dependencies, or issues with the DLL itself.