How to Fix Windows Error 0x80040100
By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-25
0x80040100 (DRAGDROP_E_NOTREGISTERED) on Windows is a drag-and-drop status code: the system is telling you Trying to revoke a drop target that has not been registered. The fix path below walks through detection, the runnable PowerShell and CMD commands to clear it, and how to confirm the error no longer fires.
| Error code | 0x80040100 |
|---|---|
| Decimal (unsigned) | 2147746048 |
| Decimal (signed 32-bit) | -2147221248 |
| Symbolic name | DRAGDROP_E_NOTREGISTERED |
| Platform | Windows |
| Subsystem | drag-and-drop (OLE Drag-and-Drop (Ole32)) |
| Severity field | Warning (top bits 10) |
| Official message (verbatim) | Trying to revoke a drop target that has not been registered. |
| Source | Microsoft MS-ERREF (HRESULT values) |
What is 0x80040100?
0x80040100 comes from the OLE drag-and-drop layer. These codes typically signal that the user cancelled the drop, that the drop target rejected the format, or that the source object lost its data between drag-enter and drop. In plain English, the system is telling you Trying to revoke a drop target that has not been registered. Microsoft documents it as a drag-and-drop value, which means applications hit it when they call into the OLE Drag-and-Drop (Ole32) stack. The DRAGDROP_E_NOTREGISTERED symbol shows up in header files, debugger output, and event log messages, so searching for it in the calling application's source or trace logs usually pinpoints where the call originated.
When does 0x80040100 appear?
The drag-and-drop layer raises this code in a few well-known scenarios. Knowing which one you are in saves an hour of guessing:
- The user pressed escape during the drag, cancelling the drop.
- The drop target does not accept any of the offered formats.
- The source data object was released before drop completed.
- The drop happened outside any registered drop target.
Re-test with a known target (Explorer window) to confirm whether the bug is in the source object or the target. If your event log shows the code firing alongside a specific component or service name, that name is the real starting point - the 0x80040100 value just tells you the class of failure.
How to fix 0x80040100
Work the steps below in order. Each one is a real, runnable PowerShell or CMD block. Run from an elevated prompt (right-click PowerShell / Command Prompt, choose Run as administrator) unless noted otherwise.
Step 1: confirm the COM class is actually registered
# Replace {<CLSID>} with the CLSID surfaced in the error log or call stack.
$clsid = '{<CLSID>}'
Get-Item "HKLM:\SOFTWARE\Classes\CLSID\$clsid" -ErrorAction SilentlyContinue
Get-Item "HKLM:\SOFTWARE\Classes\CLSID\$clsid\InprocServer32" -ErrorAction SilentlyContinue |
Select-Object Property, @{n='Default';e={$_.GetValue('')}}
:: Re-register the COM DLL from the matching-bitness command prompt
:: 64-bit:
%SystemRoot%\System32\regsvr32.exe "C:\Path\To\Component.dll"
:: 32-bit on a 64-bit OS:
%SystemRoot%\SysWOW64\regsvr32.exe "C:\Path\To\Component.dll"
Step 2: inspect DCOM launch and activation permissions
:: Opens Component Services. Navigate to:
:: Computers -> My Computer -> DCOM Config -> <your application>
:: Right-click -> Properties -> Security tab.
:: Confirm the calling identity has Local Launch + Local Activation rights.
dcomcnfg.exe
Step 3: check the launch identity can actually start the server
# Pull the configured RunAs identity for the application.
$apps = Get-WmiObject -Namespace root\cimv2 -Class Win32_DCOMApplicationSetting
$apps | Select-Object Description, AppID, RunAsUser, AuthenticationLevel |
Format-Table -AutoSize
Step 4: tail the COM events that fire around the failure
# Filter the System log for DCOM and ComBase events.
Get-WinEvent -LogName System -MaxEvents 200 |
Where-Object { $_.ProviderName -match 'DCOM|ComBase' } |
Format-List TimeCreated, Id, ProviderName, Message
If you can't fix immediately
Sometimes the failure window matters more than the root cause. While you schedule the real fix, these mitigations buy time:
- Restart the service that owns the failing call. Many
drag-and-droperrors come from a state that resets cleanly on service restart (Restart-Service <name> -Force). - Reboot the host if a kernel-side component is involved. NTSTATUS and driver-related codes often clear after a clean reboot.
- Temporarily lower the calling code's reliance on the failing path (disable the optional feature, fall back to a known-good code path, or queue the work for retry once the underlying fix lands).
- Capture a full repro with Procmon and a matching event log export so the real fix is one trace away when the maintenance window opens.
How to verify the fix worked
After applying the steps above, confirm 0x80040100 is no longer raised by the failing operation. Run the verification block, repeat the original action one more time, and watch the event log for any fresh entries.
Verify the error no longer surfaces
# 1. Re-run the original operation that produced 0x80040100.
# 2. Re-query the System log for the code and confirm no new entries land.
Get-WinEvent -LogName System -MaxEvents 50 |
Where-Object { $_.Message -match '0x80040100' } |
Sort-Object TimeCreated -Descending |
Select-Object -First 5 TimeCreated, Id, Message
# 3. Same for the Application log.
Get-WinEvent -LogName Application -MaxEvents 50 |
Where-Object { $_.Message -match '0x80040100' } |
Sort-Object TimeCreated -Descending |
Select-Object -First 5 TimeCreated, Id, Message
# 4. Confirm the calling process exited cleanly.
$LASTEXITCODE
:: If the failing operation was driven from CMD, %ERRORLEVEL% should be 0.
echo %ERRORLEVEL%
If the verification block returns no new entries that mention 0x80040100 or DRAGDROP_E_NOTREGISTERED in the time window after your fix, you can close out the incident. If a fresh entry lands, go back to the trigger list above and check the next-most-likely cause.
Frequently asked questions
What does 0x80040100 mean exactly?
It is a drag-and-drop code returned by OLE Drag-and-Drop (Ole32). In short, the system is telling you Trying to revoke a drop target that has not been registered.
Is 0x80040100 dangerous?
This is a status signal in most cases, not a breach indicator. The code is a signal, not a fault. It tells you the drag-and-drop layer rejected (or could not finish) a specific call. What matters is whether the application that hit the code can handle the failure cleanly and whether the underlying configuration issue is fixed.
Will reinstalling Windows fix 0x80040100?
Almost never. Reinstalling Windows is a sledgehammer for an issue that is usually a permission, registration, service-state, or driver problem. Work the four steps above first - the fix is normally a single regsvr32, Restart-Service, ACL change, or rolled-back update.
Is 0x80040100 the same as DRAGDROP_E_NOTREGISTERED?
DRAGDROP_E_NOTREGISTERED is the symbolic name Microsoft assigned to 0x80040100. They are the same value. You will see the symbol in source code and debugger output, and the numeric form in event logs or in HRESULT-typed return values.
Where can I find the official Microsoft documentation for 0x80040100?
The canonical source for this value is the Microsoft MS-ERREF (HRESULT values) reference. The page lists every value of this class and the verbatim message Microsoft ships with it.
Related error codes
- How to fix 0x80040101 - DRAGDROP_E_ALREADYREGISTERED
- How to fix 0x80040102 - DRAGDROP_E_INVALIDHWND
- How to fix 0x80040110 - CLASS_E_NOAGGREGATION
- How to fix 0x80040111 - CLASS_E_CLASSNOTAVAILABLE
- How to fix 0x80040112 - CLASS_E_NOTLICENSED
Related fixes
Related guides worth a look while you sort this one out:
- How to Fix Windows Error 0x80040068
- How to Fix Windows Error 0x80040069
- How to Fix Windows Error 0x8004006A
- How to Fix Windows Error 0x8004006B
- How to Fix Windows Error 0x8004006C
- How to Fix Windows Error 0x8004006D
References
- Microsoft MS-ERREF (HRESULT values): https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/705fb797-2175-4a90-b5a3-3918024b10b8
- Microsoft Learn - Win32 system error codes: https://learn.microsoft.com/en-us/windows/win32/debug/system-error-codes
- Microsoft MS-ERREF (full Windows error code reference): https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/
- Microsoft Learn - HRESULT structure: https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/0642cb2f-2075-4469-918c-4441e69c548a
- Sysinternals Procmon (live trace tool): https://learn.microsoft.com/en-us/sysinternals/downloads/procmon
Compiled from the Microsoft MS-ERREF reference and the Windows debug error reference, last verified on 2026-05-25. Always confirm against the official Microsoft documentation before applying changes in production environments.
Field notes from real Windows incidents
When I work on the 0x80040100 symptom the rhythm I lean on is the one I have built over years of these tickets, not a stack of generic advice. DISM RestoreHealth needs network or a known-good source image; the most common cause of a failed RestoreHealth is a blocked Windows Update endpoint. Reliability Monitor is the single most underused triage surface in Windows — it gives 30 days of crash history without writing a query.
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 0x80040100 symptom on Windows the cheapest signal I can land usually comes from Process Monitor (procmon), then Windows Performance Recorder, DISM and sfc, WinDbg for STOP code analysis, Event Viewer (eventvwr.msc) when Process Monitor (procmon) cannot see the layer the fault sits in, and PowerShell Get-WinEvent 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 0x80040100 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.
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 /RestoreHealthIf 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.
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.
err.exe 0xXXXXXXXX # symbolic decodeIf 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.
sfc /scannowOnly 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 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 0x80040100 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. DISM RestoreHealth needs network or a known-good source image; the most common cause of a failed RestoreHealth is a blocked Windows Update endpoint. Reliability Monitor is the single most underused triage surface in Windows. it gives 30 days of crash history without writing a query. 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 0x80040100 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 0x80040100 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.