Cannot ping or file share between wired PCs with new XB6 Gateway

[the47tesla]

I just installed an XB6 (Arris TG3482G) gateway, replacing an existing Linksys CM3024 modem and Asus RT-N66U router.  I have two PCs wired to the two LAN ports on the XB6.  The old setup was able to ping,  file share, and Windows Remote Desktop between the two wired PCs. 

Each PC (10.0.0.xx) can ping itself and the gateway (10.0.0.1) but not the other.  Windows File Explorer displays both PCs under Network, but I cannot access shared folders in one from the other.  Folder sharing permissions have not changed from the old setup, which worked fine.

Is the XB6 gateway blocking access between the wired PCs?  Is it blocking file and printer sharing?

Is this related to the Advanced/Remote Management setting in the gateway?  Currently disabled, but isn't this for HTTP internet access and not file sharing?

[the47tesla · Accepted solution]

Solved:

Windows 10 network profile setting changed itself from Private to Public when XB6 was installed, possibly due to being seen as a new network at 10.0.0.xxx rather than the old one at 192.168.xxx. Changing it back to Private fixed all ping and file sharing issues.