Double-clicking the map document in Windows Explorer does not open it in a new ArcMap session.

Description

Cause

Workaround

1. Start Windows Explorer, browse to C:\Program Files\Common Files\ArcGIS\bin\ and double-click on ArcGISFileHandler.exe to start it.
2. On the Map Options tab, select 'Open in running application'.
3. Click OK to close the ArcGIS File Handler application.
4. Start C:\Program Files\Common Files\ArcGIS\bin\ArcGISFileHandler.exe again.
5. On the Map Options tab, select 'Open in new application'.
6. Click OK to close the ArcGIS File Handler application.

Steps to Reproduce