Description
DNS_ERROR_RCODE_NAME_ERROR (hex code 0x0000251F, decimal 9503) is a Windows warning-level error code in the DNS Errors family. Microsoft surfaces this code through the Win32 API, the Common Language Runtime, the kernel, the event log, PowerShell, command-line tools (sfc, dism, gpupdate, sc), and Windows-side applications such as Outlook, Teams, Office, and System Center.
DNS name does not exist.
This page documents what triggers 0x0000251F, the most common scenarios where it appears, the likely root causes, and a step-by-step troubleshooting workflow you can run against affected endpoints. It is intended for system administrators, MSP technicians, helpdesk engineers, and anyone diagnosing Windows behavior in a managed environment.
In-depth explanation
This is a warning-severity code. The operation did not necessarily fail; Windows may have completed it with side effects, conflicts, or a state that requires user attention. It is normally safe to retry, but should still be logged so repeated occurrences can be triaged.
It is part of the DNS / WinSock error space. It surfaces in DNS Manager, nslookup, Resolve-DnsName, and any application performing name resolution.
The code can be looked up programmatically in PowerShell with [ComponentModel.Win32Exception]::new(9503).Message (for Win32 / NTSTATUS codes that map cleanly), or with net helpmsg 9503 for the legacy decimal range. For HRESULT-style codes, decode the facility and code with err.exe from the SDK or via the WinDbg !error command.
Common causes
- Target hostname does not exist or zone not authoritative.
- Recursive resolver (Active Directory DNS, public 1.1.1.1, etc.) returning SERVFAIL.
- Stale negative cache on the client — flush with
ipconfig /flushdns. - Conditional forwarder or split-horizon misconfiguration.
- DNSSEC validation failing on the recursive resolver.
Troubleshooting steps
- Verify resolution from the client:
Resolve-DnsName <hostname> -Server <dns-server>. - Flush the local cache:
ipconfig /flushdns; clear the negative cache. - Inspect the DNS server event log for SERVFAIL, REFUSED, or recursion errors.
- If conditional forwarding is in play, validate the forwarder is reachable and the zone is delegated.
- Test against a known-good public resolver (1.1.1.1, 8.8.8.8) to isolate whether the issue is local or upstream.
Decode in PowerShell
# Decode 0x0000251F (9503) in PowerShell
[ComponentModel.Win32Exception]::new(9503).Message
# Or via WinDbg / err.exe (Windows SDK)
# err 0x0000251F
# Or net helpmsg (legacy decimal range only)
# net helpmsg 9503Frequently asked questions
What does the Windows error code 0x0000251F mean?
DNS_ERROR_RCODE_NAME_ERROR (decimal 9503). DNS name does not exist.How do I decode 0x0000251F in PowerShell?
[ComponentModel.Win32Exception]::new(9503).Message in any PowerShell session. For HRESULT-style codes, use err.exe from the Windows SDK or the WinDbg !error command.Where does Windows typically log this error?
%WinDir%\WindowsUpdate.log; AD/Kerberos → Security event log on the DC; BSOD → minidump under C:\Windows\Minidump; MSI → %TEMP%\msi*.log; WMI → Microsoft-Windows-WMI-Activity). Always cross-reference the timestamp and module name with the Application and System event logs.Is this code recoverable?
Should I open a Microsoft support case for this?
Get-WinEvent export ready before opening the case.
