Windows BSOD Error 0x0000003F — NO_MORE_SYSTEM_PTES Fix

What Does This Error Mean?

The 0x0000003F blue screen means Windows has run out of Page Table Entries (PTEs). PTEs are small memory structures Windows uses to track how memory is being used. When they are exhausted, Windows cannot manage memory properly and crashes. This is called NO_MORE_SYSTEM_PTES.

Affected Models

Windows 10
Windows 11
Windows 8.1
Windows Server

Common Causes

A driver is leaking memory — consuming PTEs without releasing them, eventually exhausting the supply
You have too many devices connected that each require their own PTE allocations
A faulty or outdated storage controller driver (disk or network) is the most common culprit
Virtual memory (page file) is misconfigured or set too low for your workload
RAM is failing, causing Windows memory management to behave unpredictably

How to Fix It

Update your storage and network adapter drivers. Open Device Manager (right-click the Start button > Device Manager). Look for any devices with a yellow warning icon. Right-click each and select Update driver.

Storage controller and network adapter drivers are the most common source of PTE leaks in this specific blue screen.
Run the Windows Memory Diagnostic tool. Press Windows Key + R, type mdsched.exe, and press Enter. Choose Restart now and check for problems.

This tests your RAM for errors. Faulty RAM can cause all sorts of memory management blue screens, including this one.
Check and adjust your virtual memory settings. Right-click This PC > Properties > Advanced system settings > Performance > Advanced > Virtual memory. Choose Automatically manage paging file size for all drives.

Letting Windows manage the page file automatically ensures it has enough virtual memory headroom when physical RAM is under pressure.
Run System File Checker. Open Command Prompt as Administrator and type: sfc /scannow and press Enter. Wait for it to complete.

This scans Windows for corrupted system files and replaces them automatically. It can take 10 to 20 minutes.
Check Event Viewer for clues. Press Windows Key + R, type eventvwr.msc, press Enter. Go to Windows Logs > System and look for critical errors around the time of the crash.

Event Viewer often names the specific driver or component that triggered the crash, which tells you exactly what to fix.

When to Call a Professional

If you have updated all drivers and the blue screen keeps coming back, there may be a hardware fault. A technician can run memory diagnostics and check for failing components. Frequent blue screens (daily or more) warrant professional investigation to protect your data.

Frequently Asked Questions

What is a Page Table Entry and why does Windows run out of them?

A Page Table Entry is a tiny data structure Windows uses to map where each block of memory lives. Think of them as index cards in a filing system — every block of memory gets one. If a driver keeps grabbing PTEs without giving them back (a memory leak), the supply runs dry and Windows crashes.

How do I know which driver is leaking PTEs?

The crash dump file created when the blue screen occurs often names the responsible driver. You can use a free tool called WinDbg Preview (available in the Microsoft Store) to open the dump file. The dump file is usually located at C:\Windows\Minidump with a .dmp file extension.

Can adding more RAM fix this error?

Sometimes. More RAM means more headroom before PTEs run out. However, if the underlying cause is a driver leak, adding RAM only delays the crash — it does not cure it. Fix the driver first. If crashes still occur but less frequently, more RAM may help further.