Samsung S7 Android File Transfer problem to Mac was bad cable
Cable that came with new phone in Jan 2017 works great. Spare "Premium OEM" :) cable and charger from ebay is the problem caused files larger than say 20 to 200 meg to drop the link and kill the Andoid File Transfer link and program. Old OSX 10.7.5 Snow Leopard on a late 2006 iMac. The spare cable was supposed to be the original version, it was not the lowest cost one. :)
Cable that came with new phone in Jan 2017 works great. Spare "Premium OEM" :) cable and charger from ebay is the problem caused files larger than say 20 to 200 meg to drop the link and kill the Andoid File Transfer link and program. Old OSX 10.7.5 Snow Leopard on a late 2006 iMac. The spare cable was supposed to be the original version, it was not the lowest cost one. :)