Cannot connect to Samsung Galaxy S4 wifi hotspot from laptop
In case you still have this problem - or for anyone else who may have it: I had a very similar problem for a long time (Xperia Z1 with Android 5.1, was able to connect to the mobile hotspot from Windows Phone 8.1 and a Windows 7 Professional notebook, but not with Windows 7 Ultimate or a tablet with Windows 10). 

I was able to solve the problem by changing the encryption type from TKIP to AES (Right click on network connection to mobile hotspot>Properties>Security tab. The Security type is set to WPA2-Personal.