When you are using Windows Explorer View in SharePoint you can't MOVE a file from one site to another if it's not directly below the root site, but you can copy the file. See the different scenarios below. Working Scenario Moving files between libraries within the same site. For example: "http://sharepointsite/sites/site1/site2/library1" (source) "http://sharepointsite/sites/site1/site2/library2" (destination) Moving files between libraries across different sites as long as they are directly below the root site. For example: "http://sharepointsite/site1/library1 (source) "http://sharepointsite/site2/library2 (destination) Non-working Scenario Moving files between libraries in sub-sites that are more than 1 level below the root site. For example: "http://sharepointsite/sites/site1/site1/library1" (source) "http://sharepointsite/sites/site1/site2/library2" (destination)