Copy file from a computer not in domain to a computer in domain C++

Copy file from a computer not in domain to a computer in domain C++

I have 2 computers in which one computer is in Domain and the other one is
not in domain. I want to copy a file from a computer not in domain to a
computer in domain by providing login credentials.
I tried mapping network folder to a drive with WNetAddConnection2. Since
we will run this exe as a windows service, handling of mapped drives is a
big challenge. Are there any other ways to do network copy of file?