vb6 icon location on windows

Where can I find the orginal vb6 ( or windows ) icon? (.ico files)

I need, error, warning, question, and information icons which come up on the messagebox.

Thanks a lot.

As the icons can differ for each OS version, you can get the icons from Windows using LoadIcon() passing one of the standard icon IDs.
See http://msdn.microsoft.com/en-us/library/ms648072.aspx for details.
If you want them as .ico files, you can extract them (on your development machine) from user32.dll using a resource editor.

(Updated with corrected info from Cody Gray)

The standard Windows message box icons have changed many times across the various versions of Windows. They're included with a couple of the system DLL files, but you shouldn't try and extract them dynamically yourself. As I mentioned in a comment to another answer, the ID numbers are undocumented for a reason: namely because it's possible for them to change in future versions of Windows or even in future Windows updates. There's absolutely no reason to go through the effort trying to extract them, either. Windows will already retrieve them for you, if you ask nicely.

The nice way of asking is to use the LoadIcon function, and specify the IDI identifier of the icon you want. Windows will return an HICON value, or a handle to an icon resource.

Since you mention that you're using VB.NET, you can also use the SystemIcons class, which has static properties to return any of the common icons. This is a .NET wrapper that saves you from having to P/Invoke the LoadIcon function from the Windows API yourself.

Better yet, if you just want to display a message box containing one of the icons, all you have to do is call the MessageBox API function. Tell Windows the MB_ICON value that you want, and you're off. As before, this has already been wrapped for you by the .NET Framework in the identically-named MessageBox class.

The benefit of both of these functions is that they'll always return the correct icons regardless of the current version of Windows. A comment made attempting to clarify the question seems to suggest that you want to use the old icons on a current version of Windows. But of course, you do not want to do this. The icons have been updated throughout the Windows shell for a good reason, and your application should take advantage of them. The new icons are more clear and fit in better with the overall system theme. Additionally, if your app still uses the old icons, it will be confusing to users and look very out of place. It's always best to follow standard platform conventions, rather than trying to do "something else", even if you think your "something else" is "better" for whatever reason than the platform default. Your users will not agree, and your application will reflect your shoddy craftsmanship.

Since people who ask this type of question inevitably disagree with me and insist that they must do it anyway, and that it is a "requirement" (whatever that means), I'll point out that the old icons are not available in the newer versions of Windows. The icons have been completely replaced throughout the system for a reason. It's also strictly forbidden by the licensing agreements to extract icons from system DLL files and redistribute them with your application. Don't do this.

Also, before deciding on which icon you should display in your message box, be sure to consult Microsoft's Windows User Experience Interaction Guidelines, which provide some very handy rules on selecting the proper icon to convey the right message and fit with the Windows tone. I provide more information on that in my answer here; very much recommended reading for any Windows application developer.

Edit: It's like pulling teeth to get any more details on this question. I'm not sure why you're so secretive about what you're trying to accomplish, but note that in the future, you'll have a lot better luck including these things in your question to start with, rather than hoping people will pull it out of you. Most people aren't nearly as persistent as I am.

Anyway, you finally mention that you're doing some type of interop between VB 6 code and .NET code. That should not be relevant in the case of the message box icons used. The VB 6 MsgBox function is 100% equivalent to the Win32 API MessageBox function and the .NET MessageBox class that I discussed earlier. All of them are going to use the current system icons, and it shouldn't require any extra work to make them look the same. Ensure that you've passed the same icon specifier to all of the functions. Here's a table for convenience:

VB 6 "MsgBox" Icon Constant | VB.NET "MessageBox" Icon Identifier
---------------------------------------------------------------------------------
vbCritical                  | MessageBoxIcon.Error                
vbQuestion                  | MessageBoxIcon.Question  (DEPRECATED -- do not use)
vbExclamation               | MessageBoxIcon.Warning
vbInformation               | MessageBoxIcon.Information

Note that the "Question" style icon has since been deprecated and you should not use this value. If you're still using it in the VB 6 code, you should change that code to use a different icon (or no icon at all). The above-linked Windows User Experience Interaction Guidelines provide more details on why this icon has been deprecated and how to choose a suitable replacement.