Files without Extensions are Mapped to Application/Octet-Stream


When IIS locates a file that does not have an extension, the Content-Type that is sent back to the browser is set to application/octet-stream. There is no way to change this behavior in the user interface. The AOL Netscape browser does not display the file because of this header setting. Instead, it tries to download the file.


WARNING: If you edit the metabase incorrectly, you can cause serious problems that may require you to reinstall any product that uses the metabase. Microsoft cannot guarantee that problems that result if you incorrectly edit the metabase can be solved. Edit the metabase at your own risk.

NOTE: Always back up the metabase before you edit it.

To resolve this problem, do the following:
  1. Install the IIS Resource Kit.
  2. Run the Setup program to install MetaEdit.
  3. Start MetaEdit, open the LM tree in the left hand pane, and then open the MimeMap folder.
  4. In the right pane, double-click ID 6015 MimeMap.
  5. In the Data list box, scroll down (about half way) until you find .*,application/octet-stream.
  6. Change the value to .*,text/html.
  7. Click OK, and then close MetaEdit.
  8. Open a command window so that you can stop and restart IIS.
  9. Type the following command at a command prompt:
    net stop iisadmin /y
  10. Type the following command at a command prompt:
    net start w3svc


Add an extension to the file.


This is by design.


For additional information, click the article number below to view the article in the Microsoft Knowledge Base:

300672 HOW TO: Create a Metabase Backup in IIS 5