- 1 What Is Error 0x80040154 “Class Not Registered”?
- 1.1 ① Reset Windows Update Components
- 1.2 ② Re-register Core Update DLLs Using
- 1.3 ③ Repair System Files: SFC /scannow& DISM
- 1.4 ④ Ensure Services Are Enabled: Windows Modules Installer & TrustedInstaller
- 1.5 ⑤ Run an Elevated Batch Script to Re-register All DLLs
- 1.6 ⑥ Perform an In-Place Repair or Clean Install
- 2 Summary Table
- 3 Final Thoughts
What Is Error 0x80040154 “Class Not Registered”?
Error code 0x80040154, meaning “Class not registered”, occurs when Windows fails to find or initialize a required COM (Component Object Model) class. This can block critical operations:
- Windows Update, DISM, or SFC tools from running
- Apps or features failing to launch
- Updates stalling mid-operation
Why it happens: COM components like DLLs or OCX files may be unregistered, corrupted, missing, or mismatched in architecture. Even unrelated changes—such as uninstalling an app or deleting registry entries—can trigger this error .
① Reset Windows Update Components
Run these commands in an elevated Command Prompt:
net stop cryptSvc
net stop bits
net stop msiserver
renC:\Windows\SoftwareDistributionSoftwareDistribution.old
ren C:\Windows\System32\catroot2 catroot2.old
net start wuauserv
net start cryptSvc
net start bits
net start msiserver
Why it matters: Resetting the Update cache forces Windows to rebuild download and installation metadata, which often fixes errors caused by corrupted update files or services.
② Re-register Core Update DLLs Using
regsvr32
From Administrator Command Prompt:
regsvr32 wuaueng.dll
regsvr32 msxml3.dll
regsvr32 wups.dll
regsvr32 wups2.dll
regsvr32 wuwebv.dll
Why this helps: These DLLs power Windows Update and COM-based interactions. If they are missing or unregistered, Windows Update cannot initialize properly—leading to error 0x80040154 .
③ Repair System Files: SFC /scannow& DISM
In the same elevated command shell run:
DISM /Online /Cleanup-Image /RestoreHealth
Why it works: These tools repair system-level corruption affecting DLL registrations and update infrastructure. If system files are broken, restoring integrity often resolves COM initialization errors .
④ Ensure Services Are Enabled: Windows Modules Installer & TrustedInstaller
Open Services (services.msc) and confirm:
- Windows Modules Installer (TrustedInstaller.exe) is set to Manual or Automatic, not Disabled.
Why it matters: If Windows can’t activate crucial services, update components can fail silently before throwing errors .
⑤ Run an Elevated Batch Script to Re-register All DLLs
Community forums like ElevenForum share batch tools that automate full DLL/COM registration:
“If restoring services won’t resolve the problem, then execute the attached batch script to re‑register all DLL files.”
Why this works: It re-registers COM classes en masse, covering DLLs beyond just Windows Update. For complex errors, this is often more effective than manual steps.
⑥ Perform an In-Place Repair or Clean Install
Use official Windows installation media (USB or ISO) and select “Upgrade this PC now.”
Why it helps: This reinstalls core OS components while retaining files, apps, and settings—reshaping corrupt COM registrations cleanly, often fixing persistent 0x80040154 issues ().
Additional Tips (Tricks)
- Disable third-party antivirus/security tools temporarily—some interfere with COM or update operations ().
- Boot into Safe Mode or WinRE (Recovery Env) to run SFC/DISM using offline repair (/OFFBOOTDIR) when errors persist .
- Verify architecture mismatch: Some DLLs are 32-bit only—you may need to run regsvr32 from the SysWOW64 folder or rebuild x64 apps targeting x86 platforms .
Summary Table
| Step | Action | Why It Works |
|---|---|---|
| 1. | Reset Update components | Clears corrupt cache and services |
| 2. | Register core DLLs | Ensures COM classes are accessible |
| 3. | Run SFC & DISM | Repairs broken system files |
| 4. | Enable update services | Allows system to activate required services |
| 5. | Run full DLL registration script | Automates fixing deep COM issues |
| 6. | In-place repair or clean install | Rebuilds registry and COM structures |
| Tips | Disable antivirus, use Safe Mode, check architecture | Avoid interference and ensure correct registration |
Final Thoughts
Error 0x80040154 (“Class Not Registered”) is significant, not cosmetic—it typically points to underlying COM infrastructure damage. While simple reboot attempts won’t fix it, methodical steps like service reset, DLL registration, and in-place repair often do.
If you still encounter issues after trying these steps, feel free to share details from logs or the exact context so I can guide you further. Don’t give up—COM-based errors may be tricky, but they’re solvable with persistence!
✔️You might also find these helpful:
▶︎What Do WUSA, TrustedInstaller, and Update Orchestrator Errors Mean? Simple Guide for Windows Users
