Error Code Portal
MicrosoftWindows Win32Error code

309

ERROR_NOTIFICATION_GUID_ALREADY_DEFINED

Alternative forms: 0x00000135 · 0x135 · ERROR_NOTIFICATION_GUID_ALREADY_DEFINED · 0x80070135

What does this code mean?

Code 309 · An issue reported by Windows Win32.

Official explanation · Original text

The specified file already has a notification GUID associated with it.

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 (0-499) (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