We have a WCF service that is meant to copy an existing file from its host server to a folder on another server on a different domain (using a UNC path). We were able to do this using delegation (using LogonUser() imported from ADVAPI32.dll).
The destination file share has now been reconfigured under a DFS, and the delegation approach no longer works. There is no trust configured between the two domains (this is beyond our control).
We considered mapping a drive (we have the credentials to do it), but since the WCF service runs without an active user session, it will not work.
Is there a way for a WCF service to copy a file to a file share on another, untrusted domain?