If you found this error message like this,

You can’t connect to the file share because it’s not secure. This share requires the obsolete SMB1 protocol, which is unsafe and could expose your system to attack. You system require SMB2 or higher.  For more info on resolving this issues see: https://go.microsoft.com/fwlink/?linkid=852747

That means your server file share is requiring SMB1 protocol. But to enable SMB1 is unsafe.  it need to update windows to latest version and then you  can enable SMB1 by follow this, Go to control panel programs and then click “Turn windows features on or off”. Scrolling to SMB1.0/CIFS File Sharing Support, check box SMB1.0/CIFS Client and Server as picture below,