ErrorFindly
0x0000001BBSODCritical

0x0000001B — PFN Share Count | Blue Screen Fix Guide

PFN_SHARE_COUNT

Windows XPWindows VistaWindows 7Windows 8Windows 10Windows 11

What Does 0x0000001B Mean?

The Page Frame Number (PFN) share count for a physical page is corrupt.

Real-World Causes

  1. 1RAM hardware failure
  2. 2Driver corrupting page tables
  3. 3Internal memory manager error

Symptoms

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

DIY Fix

Beginner-friendly steps you can try at home

  1. 1Restart your computer
  2. 2Run Windows Memory Diagnostic (mdsched.exe)
  3. 3Reseat RAM modules
  4. 4Check for Windows updates

Advanced Fix

For experienced users and IT professionals

  1. 1Test RAM with MemTest86 for multiple passes
  2. 2Analyze minidump with WinDbg
  3. 3Check for memory leaks using poolmon
  4. 4Inspect physical RAM slots and modules

Frequently Asked Questions

What causes PFN_SHARE_COUNT?
The Page Frame Number (PFN) share count for a physical page is corrupt.
Can I fix PFN Share Count 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

0x0000001CPFN Reference Count0x0000004EPFN List Corrupt

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.