Delete EXD files to fix “Object library invalid” error

We have a Microsoft Word template that contains macros, which was working fine but all of a sudden in the last few days, whenever you invoke the template you get the following error:

Word has encountered a problem.

If you open the template file instead of invoking a New document from it, you get a more detailed error:

Object library invalid or contains references to object definitions that could not be found

This was obviously due to a change in our systems. After googling awhile, I found this article which explains that the error can happen after installing a certain Windows update: http://support.microsoft.com/default.aspx?scid=kb;en-us;932349. The update installs new versions of certain Visual Basic 6.0 Runtime files. The article provides a link to a cumulative update rollup which I tried, to no avail.

Upon further investigation, I found that the files had been updated fine. However, there is a corresponding EXD file that is created for each of the runtime files, when you use the controls provided by the runtime files in the Visual Basic designer. When the runtime files are updated, these EXD files are now invalid and hence this error occurs. To fix the error, you need to delete the EXD files and they will be re-created as needed.

These files should be located in the folder: %APPDATA%\Microsoft\Forms\

On Windows XP, it is usually located in:
C:\Documents and Settings\%USERNAME%\Application Data\Microsoft\Forms\

And on Windows Vista/7:
C:\Users\%USERNAME%\AppData\Roaming\Microsoft\Forms\

It was easy enough to fix for myself, but others were having this problem – so I made a script that given the username deletes the files. I had users run the script (you can post it as a link on a webpage and as long as you use Internet Explorer and low security settings it can be invoked from there):

// Function to delete EXD files from user Application Data folder
//     This is to resolve an issue with Word VBA macros that use VB runtimes, which the EXDs point to
function deleteEXDs(){
    var strToPath = "%appdata%\\Microsoft\\Forms\\";
    try {
		var fso = new ActiveXObject("Scripting.FileSystemObject");
		var shell = new ActiveXObject("WScript.Shell");
	}
    catch (err) {
        alert("Could not create ActiveXObject.\nThis script should be run from Internet Explorer, \n" +
		      "with low security settings (e.g. Intranet or Trusted Sites).");
		return;
    }

    try {
		var appdata = shell.SpecialFolders("AppData");
		var strToPath = appdata + "\\Microsoft\\Forms\\";
		var fldr = fso.GetFolder(strToPath);
		var noEXDs = true;

		for (var e = new Enumerator(fldr.Files);  !e.atEnd();  e.moveNext())
		{
			if (fso.GetExtensionName(e.item()).toLowerCase() == 'exd')
			{
				noEXDs = false;
				try {
					var filename = new String(e.item());
					e.item().Delete();
					alert('DELETED ' + filename);
				}
				catch (err)
				{
			        alert("Error - could not delete " + e.item() + ".\nDescription: " + err.description);
				}
			}
		}

		if (noEXDs) alert('No EXD files found.');
    }
    catch (err) {
        alert("Error - could not clean up EXD files.\nDescription: " + err.description);
    }
}

Edit 26 Oct 2010:
Thanks for all the positive comments!

I noticed that this solution of deleting the EXD files is now also being mentioned in the Microsoft KB article: http://support.microsoft.com/kb/957924/en-us

Edit 1 July 2011:
Thanks to the comment below by Paul M Edwards, I updated the script to use the AppData environment variable, so it should now work with Windows newer than XP.