If you are using Management Reporter Web Viewer to view reports and cannot download them to Report Viewer, it may be due to a recent security update to Internet Explorer.  In Web Viewer, when you click Download | Management Reporter Report Viewer nothing will happen.  IE may flash or blink, but Report Viewer will not open.  If that happens, check your version of IE.  If it is 11.0.9600.19301, you'll need to enable protected mode in Internet Explorer.  To do that, follow these steps:

  1. Go to Tools > Internet options > Security.
  2. Within Select a zone to view or change security settings, select Local intranet and then select Enable Protected Mode.
  3. Select Trusted sites and then select Enable Protected Mode.
  4. Select OK.

You must restart the browser after making these changes.

You can find additional information about this update to IE here:

https://support.microsoft.com/en-us/help/4489873/cumulative-security-update-for-internet-explorer-march-12-2019