When you use Internet Explorer to open a Microsoft Word 2003 document from a Web site, and close your Web browser window, or press the Back button, you are prompted for a user name and password?
NOTE: You may experience this behavior if you open a read-only Microsoft Word 2003 document directly from a Web server and then close word.
This behavior occurs because Internet Explorer is trying to write the document to the MRU (Most Recently Used) list and requires both Read and Write permissions on the document to do this.
NOTE: If you have a Web folder that points to the Web server, the Web folder will try to gain Read / Write access to the document.
To fix this behavior:
1. Copy / Paste the following to a DontAddToMRUIfURL.reg file:
2. Merge the DontAddToMRUIfURL.reg file with the registry, or run regedit /s DontAddToMRUIfURL.reg.