When using down negotiation to SMB1, access to a share using DNS alias CNAME.
Access to the server using the real name is working as expected as SMB1 do not support alias when strict name check is enable.
When using down negotiation to SMB1, access to a share using DNS alias CNAME.
Access to the server using the real name is working as expected as SMB1 do not support alias when strict name check is enable.
Change Down-Negotiation to NONE
or
Disable Strict Name Checking on the server
https://support.microsoft.com/en-us/kb/281308