Import Spreadsheet error

I receive "an unexpected error" trying to import a spreadsheet to a custom list. I am using MOSS 2007 Enterprise on a Virtual Server with Windows 2003 Enterprise. Here are the steps that I perform:

I click on "Site Actions" and select "Create"
Under "Custom Lists", I select "Import Spreadsheet"
I type the Name, Description and Select a MS Word 2003 spreadsheet.
As soon as I click "Import", I receive an error: "An unexpected error has occurred. (-2147467259)"

I have tried this with many files... all with the same results. It doesn't even make a round-trip to the server. I have tried to run a repair on the installation several times.... nothing... When I look at the source, there are no errrors that have an error code -2147467259. Anybody know how to resolve this issue

SharePoint Products and Technologies4

I saw something like this once where the site was not in the trusted sites list.

Shane - SharePoint Help

That was it! Thanks mucho...

I added the site as "Trusted" in the browser security settings and refreshed.

I have a similar error although the site is in the trusted sites.
I can choose the cells that I want to import in Excel and everything looks fine until I click import. Then a very quick response appears (<1 sec. response time) stating that no connection to the server could be established and therefore my list cannot be published. It seems like an Excel error message since it appears in a modal dialog. I'm using Office 2003 SP2 and MOSS 2007.
On our testsystem the same excel spreadsheet works fine.
Any advice
Rene