How do I connect IPhone 6 with Windows 10?

I purchased a IPhone 6 and have not been able to get the contacts and calendar information onto the Windows 10 computer system. I had it working when I used Windows 8.1 but once I upgraded to Windows 10 the system could not open the files. When I walk into the local apple store and try to explain my problem, the moment I mention Windows everyone within hearing distance runs away.