How to grant access to SQL server agent to read network location file? Description: Cannot open the datafile "Z:\Folder\File.txt".  End Error
Error Code: 0xC004701A
Under Windows Administrative Tools and Services, find the login account for the Sql Server Agent and grant that login the appropriate rights to the folder(s)/File(s)

You can also find the login account for the Sql Server Agent by using the sql Server Configuation Manager and clicking on the Sql Server Services node.