[WSL Error: "Class not registered" (Error Code: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG)]

[alwinkunjumon]

Title

[WSL Error: "Class not registered" (Error Code: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG)]

---

Description

While attempting to install WSL using the wsl.exe --install command, the following error message is displayed:

Class not registered  
Error code: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG

This prevents WSL from being installed or used on the system, effectively blocking the ability to run Linux distributions via WSL.

---

Steps to Reproduce

1. Open PowerShell as Administrator.
2. Run the command:

   wsl.exe --install

3. Observe the error message.

Example:

PS> wsl.exe --install
Class not registered
Error code: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG

---

Expected Behavior

WSL should install without any errors, enabling the use of Linux distributions on Windows.

---

Actual Behavior

The installation process fails with the following error:

Class not registered  
Error code: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG

---

System Details

• Operating System: Windows 11 Home 24H2
• Version/Build: Version 24H2 (OS Build 26100.2605)
• Software Version: WSL (not installed)
• PowerShell Version: 5.1.26100.2161
• Other Relevant Details: Virtualization is enabled.

---

Troubleshooting Steps Attempted

1. Enabled required Windows features using DISM:

   dism.exe /online /enable-feature /featurename:Microsoft-Windows-Subsystem-Linux /all /norestart  
   dism.exe /online /enable-feature /featurename:VirtualMachinePlatform /all /norestart  

2. Updated WSL:

   wsl --update  

3. Re-registered MSI installer:

   regsvr32 MSI.DLL  

4. Ran system file and image repairs:

   sfc /scannow  
   DISM /Online /Cleanup-Image /RestoreHealth  

5. Verified Windows version compatibility.

---

Logs and Debugging Information

The logs from the diagnostic script have been attached to this issue for review.

1. Download and execute the collect-wsl-logs.ps1 script in an administrative PowerShell prompt:

   Invoke-WebRequest -UseBasicParsing "https://raw.githubusercontent.com/microsoft/WSL/master/diagnostics/collect-wsl-logs.ps1" -OutFile collect-wsl-logs.ps1  
   Set-ExecutionPolicy Bypass -Scope Process -Force  
   .\collect-wsl-logs.ps1  

2. Attach the generated log file to this issue.

Attached Log File:
WslLogs-2025-01-21_09-31-20.zip

---

Additional Context

This issue prevents the installation and usage of WSL, effectively blocking access to Linux environments on this system. Any guidance or fixes would be appreciated.

---

Similar Issues

• [Class not registered Error code: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG (#11999)](Class not registered Error code: Wsl/CallMsi/REGDB_E_CLASSNOTREG #11999)
• [WSL --class not registered (#12219)](WSL --class not registered #12219)
• [Unable to install Class not registered error (#12278)](Unable to install Class not registered error #12278)

[github-actions]

Logs are required for review from WSL team

If this a feature request, please reply with '/feature'. If this is a question, reply with '/question'.
Otherwise please attach logs by following the instructions below, your issue will not be reviewed unless they are added. These logs will help us understand what is going on in your machine.

How to collect WSL logs

Download and execute collect-wsl-logs.ps1 in an administrative powershell prompt:

Invoke-WebRequest -UseBasicParsing "https://raw.githubusercontent.com/microsoft/WSL/master/diagnostics/collect-wsl-logs.ps1" -OutFile collect-wsl-logs.ps1
Set-ExecutionPolicy Bypass -Scope Process -Force
.\collect-wsl-logs.ps1

The script will output the path of the log file once done.

If this is a networking issue, please use collect-networking-logs.ps1, following the instructions here

Once completed please upload the output files to this Github issue.

Click here for more info on logging
If you choose to email these logs instead of attaching to the bug, please send them to wsl-gh-logs@microsoft.com with the number of the github issue in the subject, and in the message a link to your comment in the github issue and reply with '/emailed-logs'.

View similar issues

Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one and thumbs upping the other issue to help us prioritize it!

Closed similar issues:

• Class not registered Error code: Wsl/CallMsi/REGDB_E_CLASSNOTREG (#11999), similarity score: 0.80
• WSL --class not registered (#12219), similarity score: 0.80
• Unable to install Class not registered error (#12278), similarity score: 0.79
• Class not registered Error code: Wsl/CallMsi/REGDB_E_CLASSNOTREG (#11705), similarity score: 0.77
• wsl not responding just saying class not registered (#11892), similarity score: 0.77

Note: You can give me feedback by thumbs upping or thumbs downing this comment.

[github-actions]

Logs are required for review from WSL team

If this a feature request, please reply with '/feature'. If this is a question, reply with '/question'.
Otherwise please attach logs by following the instructions below, your issue will not be reviewed unless they are added. These logs will help us understand what is going on in your machine.

How to collect WSL logs

Download and execute collect-wsl-logs.ps1 in an administrative powershell prompt:

Invoke-WebRequest -UseBasicParsing "https://raw.githubusercontent.com/microsoft/WSL/master/diagnostics/collect-wsl-logs.ps1" -OutFile collect-wsl-logs.ps1
Set-ExecutionPolicy Bypass -Scope Process -Force
.\collect-wsl-logs.ps1

The script will output the path of the log file once done.

If this is a networking issue, please use collect-networking-logs.ps1, following the instructions here

Once completed please upload the output files to this Github issue.

Click here for more info on logging
If you choose to email these logs instead of attaching to the bug, please send them to wsl-gh-logs@microsoft.com with the number of the github issue in the subject, and in the message a link to your comment in the github issue and reply with '/emailed-logs'.

View similar issues

Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one and thumbs upping the other issue to help us prioritize it!

Open similar issues:

• Class not registered-Error code: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG (#12459), similarity score: 0.88

Closed similar issues:

• Class not registered Error code: Wsl/CallMsi/REGDB_E_CLASSNOTREG (#11999), similarity score: 0.81
• Error code: Wsl/CallMsi/REGDB_E_CLASSNOTREG (#11497), similarity score: 0.79
• Unable to install Class not registered error (#12278), similarity score: 0.79
• Class not registered (#12411), similarity score: 0.79

Note: You can give me feedback by thumbs upping or thumbs downing this comment.

[github-actions]

Logs are required for review from WSL team

If this a feature request, please reply with '/feature'. If this is a question, reply with '/question'.
Otherwise please attach logs by following the instructions below, your issue will not be reviewed unless they are added. These logs will help us understand what is going on in your machine.

How to collect WSL logs

Download and execute collect-wsl-logs.ps1 in an administrative powershell prompt:

Invoke-WebRequest -UseBasicParsing "https://raw.githubusercontent.com/microsoft/WSL/master/diagnostics/collect-wsl-logs.ps1" -OutFile collect-wsl-logs.ps1
Set-ExecutionPolicy Bypass -Scope Process -Force
.\collect-wsl-logs.ps1

The script will output the path of the log file once done.

If this is a networking issue, please use collect-networking-logs.ps1, following the instructions here

Once completed please upload the output files to this Github issue.

Click here for more info on logging
If you choose to email these logs instead of attaching to the bug, please send them to wsl-gh-logs@microsoft.com with the number of the github issue in the subject, and in the message a link to your comment in the github issue and reply with '/emailed-logs'.

View similar issues

Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one and thumbs upping the other issue to help us prioritize it!

Open similar issues:

• [WSL] Error: "Class not registered" (Error Code: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG) (#12459), similarity score: 0.88

Closed similar issues:

• Class not registered Error code: Wsl/CallMsi/REGDB_E_CLASSNOTREG (#11999), similarity score: 0.80
• Error code: Wsl/CallMsi/REGDB_E_CLASSNOTREG (#11497), similarity score: 0.78
• Unable to install Class not registered error (#12278), similarity score: 0.78
• Class not registered (#12411), similarity score: 0.78

Note: You can give me feedback by thumbs upping or thumbs downing this comment.

[github-actions]

Diagnostic information

Issue was edited and new log file was found: https://github.com/user-attachments/files/18479062/WslLogs-2025-01-21_09-31-20.zip
Detected appx version: 2.3.26.0
Detected user visible error: Wsl/CallMsi/Install/REGDB_E_CLASSNOTREG

[Swaraj468]

I have same issue right now

WslLogs-2025-03-25_18-54-10.zip

[mniami]

I have the same as well

[alwinkunjumon]

I have the same as well

Note: Check that you have updated your os

Just download the latest wsl version from github, then install wsl
My problem was solved just by doing that.