Windows 10 can’t access sysvol & netlogon shares via UNC paths.
To resolve this issue run gpedit.msc, go to
Computer -> Administrative Templates -> Network -> Network Provider -> Hardened UNC Paths, enable the policy and click “Show” button.
Enter your server name (\\servername) into “Value name” and enter the folowing text:
RequireMutualAuthentication=0,RequireIntegrity=0,RequirePrivacy=0
into the “Value” field.