Microsoft Windows Error Code 0x00000040: How to Fix It

Q: What causes Windows error 0x00000040?

Error 0x00000040 is caused by device drivers attempting to allocate memory buffers that are too small for the requested operation. Common triggers include outdated drivers, corrupted system files, faulty RAM, or recent hardware changes.

Q: Can I fix error 0x00000040 without losing data?

Yes, most fixes for this error don't require data loss. However, always back up important files before making system changes. System restore and driver updates typically preserve personal files.

Q: How do I know which driver is causing the error?

Check the Blue Screen details for driver file names, use Device Manager to identify problem devices with yellow warnings, or use BlueScreenView utility to analyze crash dump files for specific driver information.

Q: Is error 0x00000040 related to hardware failure?

While often driver-related, this error can indicate hardware issues like failing RAM, hard drive problems, or incompatible hardware. Run memory diagnostics and disk checks to rule out hardware causes.

Q: Why does error 0x00000040 happen after Windows updates?

Windows updates sometimes install incompatible drivers or change system files that conflict with existing drivers. Rolling back recent updates or updating device drivers usually resolves these conflicts.

Abstract

Windows Error Code 0x00000040 (TARGET_MDL_TOO_SMALL) is a Blue Screen of Death error that occurs when a device driver tries to allocate memory incorrectly. This critical system error typically results from faulty drivers, corrupted system files, or hardware compatibility issues.