Transferring save files between Android tablets

I just bought a new Lenovo Yoga Tab 3 Plus as a replacement for my old Acer Iconia Tab A210. I still have my old Acer and want to transfer my save game files to my new tablet. I've been informed that Helium is a good programme to use for this. I have Helium installed on both my tablet and PC, when I load up Helium on my desktop is says "waiting for device", then when I load up Helium on my tablet and enable PTP it says "Waiting for Helium Desktop application to enable application backup on your Android" ad then tells me to get Helium on my PC (which I have already done). When I load it up on my PC it just says "To enable Helium on your Android, please connect it to USB". My tablet is connected to my USB and the drivers are installed but the software on neither device is recognising the other. When I try and use Helium on my old Acer tablet, it just keeps on saying "Please connect your Android to your PC's USB... so it appears my tablet isn't being recognised by my PC

Any solutions on getting this to work?