Have used a SP3 for a year and just bought a SP4. Need help with two issues (am not a tech person so be nice): 1) Trying to link them via Bluetooth. The SP4 will recognize the SP3 but not vice versa. Both are running Windows 10. Do not have issues with other Bluetooth on the SP3 (have mouse and phone linked). Any ideas. 2) Not being a computer person this one is driving me crazy. I changed the desktop photo on the SP4 and 30 seconds later the same pic appeared on my SP3. I figured it was linking via Outlook account so I signed out of the SP3 and tried again. Same thing.