How to Fix Windows Error 0xC0030002
By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-25
| Error code | 0xC0030002 |
|---|---|
| Symbolic name | RPC_NT_SS_CHAR_TRANS_OPEN_FAIL |
| Platform | Windows |
| Error class | HRESULT |
| Official message | The file designated by DCERPCCHARTRANS cannot be opened. |
| Source | Microsoft MS-ERREF (HRESULT) |
What is 0xC0030002?
0xC0030002 is a Windows HRESULT, the 32-bit return value used by COM, OLE, and most modern user-mode subsystems. The high bits encode severity and the facility (which Windows component owns the code) while the low 16 bits carry the specific status. Apps that talk to COM, the Win32 API, or .NET interop are the most common producers. In plain English, this code says: nt ss char trans open fail. The official reference describes it like this: "The file designated by DCERPCCHARTRANS cannot be opened.". That description is the contract; the actual fix depends on which subsystem produced the value, which is what the rest of this guide walks through.
When does 0xC0030002 appear?
The same status code can come from very different code paths. Here are the scenarios I see most often when RPC_NT_SS_CHAR_TRANS_OPEN_FAIL shows up on a real machine:
- A Windows service (Print Spooler, Cluster Service, COM+) tries to talk to a remote endpoint but the RPC mapper rejects the binding string.
- MMC snap-ins like Services.msc or Computer Management hang because the target machine refuses the RPC call.
- Group Policy refresh (gpupdate /force) cannot reach a domain controller because dynamic RPC ports are blocked by a firewall rule.
- WMI queries fail with the same root cause when DCOM is broken under the hood.
- An installer that drops a service tries to register an endpoint and the RPC subsystem rejects the input.
If your environment matches more than one of these, work the fix steps in order: cheap diagnostics first, system repair second, in-place reinstall as the last resort.
How to fix 0xC0030002
Run an elevated PowerShell prompt (right-click Start, then Windows Terminal (Admin) or PowerShell (Admin)). Each block below is a copy-paste recipe; adapt the placeholders in angle brackets to your environment before running.
Restart the RPC subsystem services (PowerShell, run as administrator)
Get-Service -Name RpcSs, RpcEptMapper, DcomLaunch | Format-Table -AutoSize
# RpcSs is non-stoppable - reboot if a restart of dependent services does not clear the issue.
Restart-Service -Name 'Server' -Force
Restart-Service -Name 'Workstation' -Force
Test the RPC endpoint mapper across the network (PowerShell, run as administrator)
Test-NetConnection -ComputerName <TargetHost> -Port 135
rpcping.exe -s <TargetHost> -e 135 -P 'user,domain,*' -A 'user,domain,*' -F 3 -I 'user,domain,*' -t ncacn_ip_tcp
Re-register core DCOM components (PowerShell, run as administrator)
regsvr32.exe /s ole32.dll
regsvr32.exe /s oleaut32.dll
regsvr32.exe /s rpcrt4.dll
CMD fallback (run as administrator)
net stop "Workstation" && net start "Workstation"
rpcping -s <Target> -e 135
Pull the matching event-log entry
$code = '0xC0030002'
Get-WinEvent -LogName System -MaxEvents 1000 | Where-Object { $_.Message -match $code } | Select-Object -First 10 TimeCreated, Id, ProviderName, Message | Format-List
Get-WinEvent -LogName Application -MaxEvents 1000 | Where-Object { $_.Message -match $code } | Select-Object -First 10 TimeCreated, Id, ProviderName, Message | Format-List
Back the registry up before any edit
$stamp = Get-Date -Format yyyyMMdd-HHmm
New-Item -ItemType Directory -Force -Path 'C:\Backup' | Out-Null
reg export 'HKLM\SOFTWARE' "C:\Backup\HKLM-Software-pre-windows-error-0xc0030002-$stamp.reg" /y
reg export 'HKLM\SYSTEM' "C:\Backup\HKLM-System-pre-windows-error-0xc0030002-$stamp.reg" /y
If you can't fix immediately
Reduce the blast radius until the change window opens: stop the service that raises the error, isolate the host from production traffic, or fall back to a known-good snapshot. A short workaround beats a rushed change on a Friday night.
# Pause the affected service and capture state before changing anything.
Get-Service | Where-Object Status -eq 'Running' | Where-Object Name -match '<service-keyword>' | Stop-Service -Force -PassThru
Get-ScheduledTask | Where-Object State -ne 'Disabled' | Where-Object TaskName -match '<task-keyword>' | Disable-ScheduledTask
How to verify the fix worked
Work through these checks in order. If any one fails, repeat the matching fix step before moving on.
- Rerun the MMC snap-in or the script that produced the error and confirm the call returns a result.
- Test-NetConnection on port 135 should return TcpTestSucceeded : True.
- Get-Service RpcSs, RpcEptMapper, DcomLaunch should report Status = Running on the target machine.
Frequently asked questions
What does 0xC0030002 mean exactly?
The Windows documentation defines it as a hresult that signals nt ss char trans open fail. In day-to-day terms, it is the operating system telling a calling program that the request cannot complete in the current state. The fix is almost always about restoring the state the caller expected, not about removing the code itself.
Is 0xC0030002 dangerous?
On its face the message is informational, not destructive. The status code is a symptom, not the disease. The danger is in what produced it: a corrupted driver, a flaky disk, an exhausted resource, or a permission boundary that is wrong. Read the event-log context around the code before assuming the worst.
Will reinstalling Windows fix it?
Usually no, and it is the wrong first move. A clean install removes the entire configuration that produced the error, which makes it look fixed for a few days while you reinstall apps and drivers. The same condition tends to come back the moment the original workload is restored. Work the fix steps above before you reach for the install media.
What is the difference between 0xC0030002 and the symbolic name RPC_NT_SS_CHAR_TRANS_OPEN_FAIL?
They are the same value. 0xC0030002 is the numeric form a developer prints, and RPC_NT_SS_CHAR_TRANS_OPEN_FAIL is the C/C++ constant defined in the Windows headers. Tooling that consumes one will accept the other; the lookup is deterministic.
Where can I look up other HRESULT codes?
Microsoft maintains the full reference at MS-ERREF. For Win32 error names there is the System Error Codes index. Both are searchable by hex value and by the symbolic name.
Related error codes
Related fixes
Related guides worth a look while you sort this one out:
- How to Fix Windows Error 0xC0020057
- How to Fix Windows Error 0xC0020058
- How to Fix Windows Error 0xC0020062
- How to Fix Windows Error 0xC0020063
- How to Fix Windows Error 0xC0020064
- How to Fix Windows Error 0xC0030001
References
- Microsoft Learn - HRESULT reference: https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/705fb797-2175-4a90-b5a3-3918024b10b8
- Microsoft MS-ERREF (full Windows error code reference): https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/
- Microsoft Learn - System Error Codes index: https://learn.microsoft.com/en-us/windows/win32/debug/system-error-codes
- Microsoft Learn - Event Logging on Windows: https://learn.microsoft.com/en-us/windows/win32/eventlog/event-logging
Field notes from real Windows incidents
When I work on the 0xC0030002 symptom the rhythm I lean on is the one I have built over years of these tickets. DISM RestoreHealth needs network or a known-good source image; the most common cause of a failed RestoreHealth is a blocked Windows Update endpoint. STOP codes look terrifying but the first DWORD almost always points directly at the responsible driver. Windows error codes come in a handful of families; once you recognise the family, the doc page is one search away.
Tools I actually reach for
For the 0xC0030002 symptom on Windows the cheapest signal I can land usually comes from Reliability Monitor (perfmon /rel), then Windows Error Lookup Tool (err.exe), PowerShell Get-WinEvent, WinDbg for STOP code analysis when Reliability Monitor (perfmon /rel) cannot see the layer the fault sits in, and DISM and sfc for the cases where neither of those answers cleanly. That ordering is not academic. It matches the layers the failure tends to surface through, so the cheap signal lands first and the heavier tooling only comes out when the simpler answer does not hold up under scrutiny.
Verification I run before I close the ticket
Before I mark the 0xC0030002 symptom resolved on a Windows unit, the verification loop below is what I actually run. Each step proves a different layer is green, and the order matters - the cheap checks gate the more expensive ones.
Get-WinEvent -FilterHashtable @{LogName='System'; Level=1,2; StartTime=(Get-Date).AddDays(-7)}If that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
wevtutil epl System system.evtx # export for offline reviewIf that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
DISM /Online /Cleanup-Image /RestoreHealthOnly when every line above runs clean do I close the ticket and update the runbook with the timestamps.
Where I check first when the docs disagree
When two sources contradict each other on a Windows detail, the disambiguation order I lean on is stable. I usually start at learn.microsoft.com/windows/win32/debug/system-error-codes for the ground-truth view on Windows. I usually start at support.microsoft.com for the ground-truth view on Windows. I usually start at techcommunity.microsoft.com/category/windows for the ground-truth view on Windows. I usually start at github.com/microsoft/Windows-Driver-Frameworks for the ground-truth view on Windows. Random blog posts and reseller wikis are signal, not ground truth, and I treat them as such until the references above either confirm or contradict the claim.
Pitfalls I have walked into on this exact path
The shortcuts that look smart on the 0xC0030002 symptom have a habit of biting back. The pitfalls below are the ones I have personally walked into on a Windows unit, not things I read about. Windows error codes come in a handful of families; once you recognise the family, the doc page is one search away. STOP codes look terrifying but the first DWORD almost always points directly at the responsible driver. When in doubt I revert to the slower path that the manual prescribes - the time I save by skipping it is always smaller than the time I spend cleaning up afterwards.
What I tell the next on-call
When I hand the 0xC0030002 symptom off to the next person on rotation, the three lines I leave in the runbook are these. First, the symptom signature for Windows on the Windows family - not a paraphrase, the exact string that surfaces. Second, the diagnostic that gave the highest signal in the least time. Third, the exact verification command whose green output justified closing the ticket. That trio is what turns a one-off fix into a runbook entry the next engineer can use without paging me at three in the morning.
I also add a one-line note on the cost of getting this wrong. For the 0xC0030002 symptom on a Windows unit, the cost is rarely the replacement part. It is the downtime, the second site visit, and the trust deficit you spend with whoever owns the asset when the fix does not hold. That framing keeps the next on-call from choosing the cheap-looking shortcut that ends up costing the most in elapsed hours and goodwill.