Can't delete PowerPoint document from server

Hello,

I am using Office 2007 on Vista. A couple of weeks ago I saved some slideshows to my company's server.

Now in that folder, and only in that folder, the documents 'say' that they are already opened. Yet every time I try and open one, either the server of the document start 'not responding.' I cannot even rename the documents.


I really need to delete these documents and I cannot figure out how. The only thing I did differently was that I made copies and saved them on my desktop but I deleted those.


Anyone know how to help me?