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's name (\\myservername)
into "Value name" and enter the following text "RequireMutualAuthentication=0,RequireIntegrity=0,RequirePrivacy=0"
wihtout quotes into the "Value" field.