Hi,
I have host Offline Library Sample in our IIS,after the documents have been downloaded and disabled internet connection,then view the document getting error.
Please find the attcahed error and manifest(test.appcache) file for your reference.
Add MIME type in my web.config,
<mimeMap fileExtension=".appcache" mimeType="text/cache-manifest" />
How to host Offline Library Sample on an IIS web server?