SOLVED (for me anyway): I was having a similar issue connecting my Bose QuietComfort 35 wireless headphones to my Dell Latitude E7450 laptop running Windows 7 Pro (64bit). I ran all important and optional Windows updates until I was completely up to date. During adding a new device setup, the laptop recognized the headphones but failed to correctly install the necessary Bluetooth peripheral drivers. Long story short, what ended up working for me was to install the Intel® Wireless Bluetooth® technology-based drivers version 19.11.1639 for the Intel® wireless card that's in the Intel® NUC Kit DN2820FYKH using Windows 7. Here is the link:
Before I ran the Intel setup, I removed my headphones from the list of installed devices. I then ran the Intel setup and rebooted my laptop. After startup, I began the process to add a new device again and it successfully connected to the Bose QC35 wireless headphones with no driver related issues. From the list of connected devices, I right clicked on the Bose headphone icon and selected "Services". The connection window popped up and I started the operation to "Listen to Music". - VOILA !!!
Hope this helps anyone else experiencing Bluetooth connection issues with the Bose QuietComfort 35 wireless headphones on a Windows PC.
Good Luck! JPAUL2416