I have a PC running Windows 10 which also acts as our home server. We want to access files on the server but keep them secure to visitors on the LAN. My wife has a W10 laptop and want to access these files without any hassle - it should Just Work. Each PC has its own users set up (ie different usernames / passwords), plus we have users on the main PC.

Homegroups just don't work properly, in my experience. I managed to eventually get the laptops to join but they can't see any other PCs in the homegroup. I checked firewall settings, ran the homegroup / network troubleshooter, nothing. I tend to open things up using advanced network settings so my Kodi R.Pi2 can access the video file shares without passwords. I'm open to suggestions to get it working but pretty sick of them.

How else can I share the files? Is it possible to create password protected share then map the shares each time the laptop logs in using a script in the startup folder? Not having to type a password in each time is key, not bothered if it's saved to the laptop.

The only other way I can think of is Bittorrent Sync, which works remarkably well, but that means copying everything to the laptop and there's a lot of images and such that it doesn't make sense for. It also represents a risk, as if something goes wrong with her PC (virus/ransomware) it could more easily corrupt the main drive than with a shared drive. I of course have backups (offsite disks and online for critical stuff) but it would be a hassle.