Error Code Portal
MicrosoftWindows Win32Error code

609

ERROR_BAD_DLL_ENTRYPOINT

Alternative forms: 0x00000261 · 0x261 · ERROR_BAD_DLL_ENTRYPOINT · 0x80070261

What does this code mean?

Code 609 · An issue reported by Windows Win32.

Official explanation · Original text

{Invalid DLL Entrypoint} The dynamic link library %hs is not written correctly. The stack pointer has been left in an inconsistent state. The entrypoint should be declared as WINAPI or STDCALL. Select YES to fail the DLL load. Select NO to continue execution. Selecting NO may cause the application to operate incorrectly.

Troubleshooting and diagnostic links

First check that the document's product, version, and environment match your situation.

Source and terms of use

System Error Codes (500-999) (WinError.h) ↗

Creator: Microsoft and MicrosoftDocs contributors
License: Creative Commons Attribution 4.0 International
Checked on: 2026-11-12

Modifications: Extracted numeric codes, symbolic names and English message text; converted Markdown/HTML to plain text and normalized whitespace; added Korean product context, namespace labels, status classification and separately labeled official links. No machine translation of message text.

Source details · Original licenses and notices