Check and Repair Disk Errors: Open Command Prompt as Administrator
👇 See all 3 solutions below
What is Error 766?
Windows System Error Code 766, known as ERROR_DBG_EXCEPTION_HANDLED, is a File & Disk error that occurs during file system and disk I/O operations. The error indicates that: Debugger handled exception. When this error is encountered, the Windows operating system was unable to complete the requested operation within the file management subsystem. The error code 766 is returned by the GetLastError() function and provides developers with a specific identifier to diagnose the root cause of the failure. The symbolic name ERROR_DBG_EXCEPTION_HANDLED maps directly to this numeric code and is commonly referenced in Microsoft documentation, developer forums, and system logs. Understanding this error and its context within file system and disk I/O operations is essential for effective troubleshooting.
Common Causes
- System resource conflict: Debugger handled exception.
- The file or directory does not exist or was moved
- Insufficient permissions on the target
- Disk has bad sectors or is full
Fixing Permission Denied (0x80070005) and Access Violation Errors
An encyclopedia on Windows NT File System (NTFS) permissions, taking ownership via command line, and surviving 0x80070005 Access Denied errors.
Read the full guide →Step-by-Step Solutions
- Open Command Prompt as Administrator
- Run: chkdsk C: /f /r (replace C: with affected drive)
- Type Y to schedule scan on next restart
- Restart and wait for the scan to complete
Video Tutorials
Diagnostic Command
Run this PowerShell command to find related events in your system log:
Get-EventLog -LogName System -Newest 20 | Where-Object {$_.Message -like "*766*" -or $_.Message -like "*ERROR_DBG_EXCEPTION_HANDLED*"} | Format-List
💡 Open PowerShell as Administrator, paste the command above, and press Enter.
Prevention Tips
- Back up important files regularly
- Run CHKDSK periodically
- Keep 15%+ free space on system drive