By default, Internet Information Services (IIS) will not display files which have no extensions. This can be easily remedied by adding the MIME type to IIS for these particular files.
Open IIS by navigating to Start à Administrative Tools à Internet Information Services (IIS) Manager.
Click the plus sign next to the server name, and then the plus sign next to the Web Sites folder, right-click on the web site which you would like to enabled no-extension filenames for, and choose Properties.
Click on the HTTP Headers tab, and then click on the button which says MIME Types.
Click New.
In the new window, you will see fields for Extension and MIME Type. The information to enter into these fields are as follows:
Extension: .*
MIME Type: applications/octet-stream
Click OK, then OK again, and then OK once more to close out of the web site properties window. IIS should now be configured to display file types which do not have extensions.