Occasionally for no reason I shut the machines down and the next day I get the windows can’t join home group or one machine don’t see one of the others or you can join the home group but can’t see the shares and a host of other weird anomaly. The last time they zoned out I could not see one of the pc’s from the laptop. Long story short, I re shared my shares one at a time and as I did they popped up and could be seen. The thing is when I checked the folders they were already shared. Worked for this problem. Windows troubleshooter found no problems.

Hi, Were you prompted any error messages when you tried to join the Home group failed? You may also find out in Event Logs. And Have you already checked your network status? These may be caused you issue. I would like to share a guidance about how to set up Home Group with you. Please refer to the following link: http://crave.cnet.co.uk/software/how-to-set-up-and-configure-a-homegroup-in-windows-7-49303968/ . Also, you may try to disable SMBv2 or your Anti-Virus and Firewall software to have a try. I suspect your issue may be caused by the Firewall blocking. So please check it.