CODEWITHSUNDEEP
c#windowswmiwmi-query
Guillaume V
Guillaume V

Reputation: 1081

c# 'Invalid class' in a simple WMI query

I will like to find some result after this query, but in the beginning of the foreach loop, the error "invalid class" occur.

string wmiQuery = string.Format("SELECT * FROM Win32_Process");
var searcher = new ManagementObjectSearcher(wmiQuery);
var wmiResults = searcher.Get();

foreach (ManagementObject retObject in wmiResults)
 {
   Console.WriteLine("[{0}]\tName: {1}", retObject["ProcessID"], retObject["Name"]);
 }

I use window 7 64, and i wonder if Win32_Process exists. I also use wmi code creator download it from http://www.microsoft.com/downloads/en/details.aspx?familyid=2cc30a64-ea15-4661-8da4-55bbc145c30e&displaylang=en but i dont find any Win32_Process.

Somebody has an idea ?

Upvotes: 17

Views: 29128

Answers (5)

RadheShyam
RadheShyam

Reputation: 51

The following steps resolved my Invalid class issues

  • run from an elevated cmd prompt:

  1. cd C:\Windows\System32\Wbem

  2. for /f %s in ('dir /b *.mof *.mfl') do mofcomp %s

  3. for %i in (*.dll) do regSvr32 -s %i

  4. net stop winmgmt /y

  5. net start winmgmt

  6. gpupdate /force

(VPN should be ON for step 6 if you are on corporate machines)

Upvotes: 5

JMIII
JMIII

Reputation: 404

Just to add as this is first thing that pops up on google search and having issue myself here C# wmi query exception invalid class using ManagmentObjectSearcher

Not all WMI providers have a 32 bit and 64 bit version. You may get invalid class if running a 32 bit application on 64 bit machine. I know that is not the case in this particular situation since Win32_Process has a 32 bit and 64 bit provider but figured it might be useful for some arriving here.

Upvotes: 1

Michiel de Wolde
Michiel de Wolde

Reputation: 295

In my opinion the exception does not sufficiently state the problem. The code below works. If you for example omit "\cimv2" in the scope the exception occurs. If you for example erroneously select from "Win32_Processes" the exception also occurs. Hence at least make sure the scope is correct and the query is correct.

ManagementScope scope = new ManagementScope(@"\\localhost\root\cimv2");
ObjectQuery query = new ObjectQuery("SELECT * FROM Win32_Process");
ManagementObjectSearcher searcher = new ManagementObjectSearcher(scope, query);
foreach (ManagementBaseObject eachObject in searcher.Get())
{
    Console.WriteLine("Value: {0}", eachObject);
}

Upvotes: 0

Guillaume V
Guillaume V

Reputation: 1081

I solve my problem. It seem that my WMI was corrupt. After testing WMI with this step:

  1. Click Start, click Run, type wmimgmt.msc, and then click OK.
  2. Right-click WMI Control (Local), and then click Properties.

I saw Win32_Process was a invalid class I follow this step for repair my WMI, and it work

1) In the start menu type "cmd"

2) Type "net stop winmgmt" and press Enter

3) Open a Windows Explorer and locate the path to C:\ windows\system32\WBEM\ folder and rename the Repository folder to something else like RepositoryOLD (right click and choose 'Rename Folder').

4) restart the computer

5) In the start menu type "cmd"

6) Type "net stop winmgmt" and press enter

7) Type "winmgmt /resetRepository" and restart the computer.

Upvotes: 34

Igor Turman
Igor Turman

Reputation: 2205

As dominus suggested, use the Process class:

...
Process[] processes = Process.GetProcesses();

foreach (Process process in processes)
    Console.WriteLine(process.ProcessName);
...

Upvotes: 2

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