Error displaying control in IE

I'm getting an error when displaying the control in IE 7 on some machines, but not others. I'm testing using the example pages provided, and for some users the control works perfectly, while others get the error:

Line: 94
Error: 'grid.table' is null or not an object.

It seems like it must be related to the settings in IE, since it seems to work fine in Firefox. I've tried comparing the IE security settings between computers where it does and doesn't work, but i'm not having any luck finding the cause.

Do you have any custom javascript on the same page that may interfere?

In scripting section on the security settings, do you see any option disabled?

You can try the following modifications and see if the control is displayed:

Open FileVistaControl\scripts\filevista.js and find these two different lines:

if(grid.table)grid.table.style.cursor="progress";

if(grid.table)grid.table.style.cursor="pointer";

Comment these lines out by replacing them with the following lines respectively:

/*if(grid.table)grid.table.style.cursor="progress";*/

/*if(grid.table)grid.table.style.cursor="pointer";*/

If the problem continues, please send a screenshot via email.

The page hosting the FileVista control is running in a virtual directory within a sharepoint website, but the issue occurs when i access the page directly as well as from within sharepoint, so i don't think it's being caused by other javascript interfering. There's nothing else on the aspx page, just the FileVista control.
I tried commenting out the two lines, i no longer get the grid.table error, instead i get a popup saying:

There was a problem retrieving the XML data:
Internal server error (Error 500)

I turned on the debug setting, this produced the same message but with an exception message and stack trace, i'll send you a screenshot by email.

I just read another post on this forum relating to sharepoint-based sites, it says that the httpmodule line needs to be moved to the main web.config file for the site, and that in order to do this the assemblies need to be strongly named. I don't have a source code licence, would it be possible for you to provide strongly named assemblies for use in this situation?

Daniel,
I have sent you the strongly named DLLs, let me know the results.

Thanks Cem, i moved the httpmodule line into the sharepoint web.config and added the assemblies to the GAC, unfortunely it looks like that was not the cause of the issue, i'm still getting the same error that i sent you a screenshot of. The page still works fine from Firefox and some pc's with IE though.

The error in the screenshot means there is an error passing a parameter to web service method.

Are you sure you included the below required setting in your web.config:

        <webServices>
            <protocols>
        <add name="HttpPost" />
            </protocols>
        </webServices>

Yes, it's definitely there. I tested with the example code, the web.config is exactly the same as that except for the httpmodule part which i just moved. 

In this case, the problem seems to be about the browser (IE7) and not the server settings.

I suspect that this may be caused by a new setting in IE7. Can you please check if the option "Enable native XMLHTTP support" in the Advanced settings tab of the Internet Options dialog box, is enabled or not.

Please also let me know the exact versions of IE7 which causes the error or not.

By the way, even if this option is same for both browsers, browsing locally and remotely may make a difference so I recommend you to test with option both enabled and disabled in any case.

I found the cause of the issue, it was related to authentication. The page hosting the filevista control was in a virtual directory which allowed anonymous access, but it was being accessed from a page in sharepoint which uses windows authentication. I think that IE was trying to use the authenticated session when accessing the web service instead of the anonymous session, which is why it couldn't find the parameters. It seems to have been fixed by changing the filevista page to require authentication too.
Thanks for your help,
Daniel