ErrorFindly
0x8007003ASystemMedium

Error 0x8007003A — Bad Network Response (ERROR_BAD_NET_RESP) | Windows System Error Fix

Windows 11Windows 10Windows Server 2022

What Does 0x8007003A Mean?

The specified server cannot perform the requested operation. The network response was invalid or unexpected.

Real-World Causes

  1. 1SMB protocol version mismatch between client and server
  2. 2Network hardware corruption of packets
  3. 3Server-side application error returning malformed response
  4. 4Incompatible network configuration between systems

Symptoms

  • ⚠Network file operations fail with bad response error
  • ⚠Cannot access certain shared folders
  • ⚠File transfers abort with network error
  • ⚠Intermittent connectivity to specific servers

DIY Fix

Beginner-friendly steps you can try at home

  1. 1Restart both client and server machines
  2. 2Check for SMB version compatibility
  3. 3Update network adapter drivers
  4. 4Disable SMB signing temporarily to test

Advanced Fix

For experienced users and IT professionals

  1. 1Capture network trace with Wireshark to analyze the malformed response
  2. 2Check SMB dialect negotiation with 'Get-SmbConnection' in PowerShell

Frequently Asked Questions

What is SMB?
Server Message Block (SMB) is the protocol Windows uses for file sharing over a network. Different versions (SMB1, SMB2, SMB3) exist, and mismatches between client and server can cause errors.

Related Error Codes

0x80070039Unexpected Network Error (ERROR_UNEXP_NET_ERR)0x80070035Bad Network Path (ERROR_BAD_NETPATH)

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.