Windows BSOD Error 0x00000027 — RDR_FILE_SYSTEM Fix

What Does This Error Mean?

The 0x00000027 blue screen error means Windows' network redirector driver crashed. The network redirector is the part of Windows that lets your computer access files on a network share (like a shared folder on another PC or a NAS device). This crash often happens during file transfers over the network or when accessing shared drives. It can be caused by faulty network drivers, a bad network connection, or a third-party security program interfering with network file access.

Affected Models

Windows 10
Windows 11
Windows 8.1
Windows Server 2016
Windows Server 2019

Common Causes

Corrupted or outdated network adapter driver causing the redirector to crash
A third-party antivirus or firewall interfering with Windows network file system operations
Faulty network hardware such as a failing network card or a bad ethernet cable
Corrupted Windows system files affecting the network redirector (rdr.sys) file
SMB (file sharing) protocol conflict between the Windows version and the network device being accessed

How to Fix It

Update your network adapter driver. Right-click the Start button and open Device Manager. Expand 'Network adapters,' right-click your network adapter, and select 'Update driver.' Also visit your computer manufacturer's support site and download the latest network driver for your specific model.

An outdated or buggy network driver is the most common cause of RDR_FILE_SYSTEM crashes.
Run the System File Checker to repair corrupted Windows system files. Open Command Prompt as Administrator (right-click Start > Windows Terminal Admin or Command Prompt Admin) and type: sfc /scannow and press Enter. Wait for the scan to complete.

SFC checks all protected Windows system files including network system files and repairs any corruption it finds.
Run DISM to repair the Windows component store. In an Administrator Command Prompt, type: DISM /Online /Cleanup-Image /RestoreHealth and press Enter. This downloads and replaces any corrupted Windows component files.

DISM requires an internet connection. It takes 10-30 minutes to complete. Run SFC again after DISM finishes.
Temporarily disable your antivirus or firewall software and see if the crashes stop. Some security products intercept network file system calls in ways that can conflict with Windows' network redirector. If crashes stop with the antivirus disabled, contact the antivirus vendor for an update or configure an exclusion.

Disabling antivirus is a diagnostic step only — don't browse the internet while disabled. Re-enable it promptly after testing.
Check your physical network connection. Try a different ethernet cable. If using Wi-Fi, try switching to a wired connection. Also check the network switch or router — a faulty port can cause intermittent packet errors that crash the network redirector during heavy file transfers.

The 0x00000027 crash often happens specifically during large file transfers to or from a network share. Testing with a different cable and port is quick and free.

When to Call a Professional

If updating drivers and running SFC doesn't stop the crashes, a technician can check your network hardware and analyze the minidump crash files. Minidump analysis identifies exactly which driver or file caused the crash. A technician can examine these files in WinDbg (a Microsoft debugging tool) and tell you precisely what failed.

Frequently Asked Questions

What is the Windows network redirector?

The network redirector (also called the SMB client) is the Windows component that handles access to files stored on other computers or network devices. When you open a shared folder on another PC, map a network drive, or access a NAS storage device, the redirector handles all of that communication. A crash in the redirector (rdr.sys) causes a blue screen because it operates at the kernel level — the most critical level of Windows.

Does 0x00000027 only happen when accessing network shares?

Usually, yes — RDR_FILE_SYSTEM crashes are almost always triggered by network file system activity. If you crash consistently when opening a specific network folder or during a network file transfer, that's a strong sign it's this bug. If you're crashing at random times unrelated to network activity, a different cause (like bad RAM) may be involved.

How do I find the crash dump file to get more information?

Windows saves a minidump file each time it crashes to C:\Windows\Minidump. Each file is named with the date and time of the crash. You can open these with WhoCrashed (a free tool at resplendence.com) which reads the dump file and explains in plain English which driver caused the crash. This helps you know exactly which driver to update or remove.