ErrorFindly
0x00000040BSODCritical

0x00000040 — Target MDL Too Small | Blue Screen Fix Guide

TARGET_MDL_TOO_SMALL

Windows XPWindows VistaWindows 7Windows 8Windows 10Windows 11

What Does 0x00000040 Mean?

A driver specified a Memory Descriptor List (MDL) that was too small for the requested operation.

Real-World Causes

  1. 1Driver bug in buffer management
  2. 2Corrupted MDL structure
  3. 3Incorrect I/O buffer size calculation

Symptoms

  • ⚠Blue screen with stop code TARGET_MDL_TOO_SMALL
  • ⚠System reboots unexpectedly
  • ⚠Possible data loss from unsaved work

DIY Fix

Beginner-friendly steps you can try at home

  1. 1Restart your computer
  2. 2Update or roll back recently installed drivers
  3. 3Run System File Checker (sfc /scannow)
  4. 4Check Windows Update for driver updates

Advanced Fix

For experienced users and IT professionals

  1. 1Analyze crash dump with WinDbg
  2. 2Run Driver Verifier to isolate faulty driver
  3. 3Use Safe Mode to uninstall problematic drivers
  4. 4Check Event Viewer for related errors

Frequently Asked Questions

What causes TARGET_MDL_TOO_SMALL?
A driver specified a Memory Descriptor List (MDL) that was too small for the requested operation.
Can I fix Target MDL Too Small myself?
In many cases yes. Start with basic troubleshooting like restarting, updating drivers, and running System File Checker. If the issue persists, advanced analysis of crash dumps may be needed.

Related Error Codes

0x0000002AInconsistent IRP0x00000035No More IRP Stack Locations

About the Author

Windows Troubleshooting Team

Verified against official Microsoft documentation and real-world diagnostic data. Error behavior confirmed across Windows 10, Windows 11, and Windows Server.