How to fix Error 412 on Windows 11

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Troubleshooting Guide: Error 412 – Invalid Offset and Length Combination in Encrypted Data Info Block

Why This Error Happens

Error 412 occurs when the Encrypting File System (EFS) API calls (such as ReadEncryptedFileRaw or WriteEncryptedFileRaw) receive a mismatched or corrupted offset/length parameter while processing the $EFS metadata stream of a file. This typically happens due to corruption in the file’s EFS metadata, an interrupted backup/restore operation on an encrypted file, or a mismatch between the encryption info block and the actual raw data buffer size. It can also surface when third-party backup tools improperly handle EFS-encrypted files during transfer between volumes or systems.

Step-by-Step Resolution Guide

  1. Verify File Encryption Status
    Right-click the affected file → Properties → Advanced → check if “Encrypt contents to secure data” is enabled. Note this before making changes.

  2. Decrypt and Re-encrypt the File

  • Open Command Prompt as Administrator.
  • Run: cipher /d "C:\Path\To\YourFile.ext" to decrypt the file.
  • Copy the file to a temporary location on the same NTFS volume.
  • Re-encrypt using: cipher /e "C:\Path\To\YourFile.ext"
  1. Run CHKDSK to Repair File System Corruption
  • Open Command Prompt as Administrator.
  • Run: chkdsk C: /f /r
  • Restart the system if prompted to allow the scan to complete before Windows loads.
  1. Rebuild the EFS Certificate Database
  • Export your current EFS certificate: certmgr.msc → Personal → Certificates → right-click your EFS cert → All Tasks → Export (include private key).
  • Remove the corrupted certificate, restart, then re-import it via double-click on the .pfx file.
  1. Use a Different Backup/Transfer Method
    If the error occurs during backup software operations (e.g., Robocopy, third-party imaging tools), switch to a tool that explicitly supports raw EFS APIs (like robocopy /EFSRAW) or disable encryption before transferring, then re-enable it post-transfer.

Alternative or Verification Steps

  • Verify the fix: Attempt to open, copy, and back up the file again without triggering Error 412; check Event Viewer (Windows Logs > Application) for absence of related EFS error entries.
  • Alternative fix: If the file remains inaccessible, restore it from a known-good backup taken before encryption was applied, then re-encrypt it fresh using cipher /e.