Making IIS 7 serve MrSID Files

Until IIS 6 in order to serve MrSID files all you had to do was assign the proper NTFS permissions to the folder where the files were located and create a virtual directory in IIS. If you only do that and try to access a URL to an MrSID file on II 7 you´ll get a “404 - File or directory not found.” . The error message is confusing since the directory does exist. Finally figured there where restrictions with the MIME type, it seems IIS 7 only serves MIME you specifically declared.

To declare a new MIME type for MrSID you have to add an additional step.

1. Open the IIS Manager

2. Click on the virtual directory or directory

3. Click on MIME Types

4. Click on Add…

5. Fill the File name extension as .sid and the MIME type as application/octet-stream

6. Click Ok.

Now you should be able to access your MrSID via an URL.