When running the installable cloud application, you may fail to access the JSON file (such as launchSettings.json).
Cause:
The .json file extension is not added to the MIME type list in IIS, so the IIS server does not allow the client to access the launchSettings.json file in the CloudAppPublisher\CloudAppInstall folder.
Solution:
Step 1: In the IIS Manager, select the Web site that hosts the installable cloud application.
Step 2: In Features View, double-click MIME Types; then in the Actions pane, click Add, and then in the Add MIME Type dialog box, type the file name extension in the File name extension text box, for example, type .json, and type a MIME type in the MIME type text box, for example, application/json, and click OK.
