Are the laptops on the same domain as the server? What level is the domain set at? All using the same authentication? Is the user on the laptop setup in the correct permission groups in AD? Does the share have the right permissions as well?
If this is a 2003 domain then I wonder if you need to make some changes to it to support Windows 10 security, but the other thing is - is Windows 10 supported in a 2003 domain? Perhaps a server/domain expert can advise? More in depth areas where my knowledge dwindles a little, sorry.