Before any one asks the obvious question if the prompt is elevated and run as administrator, the answer is....yes.
I have a server called Server-A, where all of my scripts are located in D:\testfolder. So I do a pssession to the server and go to the directory where I have my ps1 file, if I try to execute the script, I get the error below when I try that.
What the script does is a very simple copy-item command from Server-B\testfolder to Server-C\test-folder. I have no problems with access to the folders from a normal Windows server GUI or even my own client as long as the administrator credentials are correct.
This server runs Server 2012 R2, if I run the script directly from the server every thing works perfect, but not if I do a pssession from my client machine with elevated administrator rights. How can this be fixed?
You're may be running into what's called the "Second Hop" problem. Review "Secrets of PowerShell Remoting" (free ebook) for details. Basically, once you remote to Server-A, it can't access non-local resources, including a path on Server-B or Server-C.
This wouldn't be the same through the File Explorer GUI, since it handles credentials entirely differently. And this has nothing to do with admin rights; it has to do with the ability to delegate your credential across multiple hops.