Please share the exact folder you are trying to move a file to. Is it the root of "C:\Program Files", or is it some subfolder like C:\Program Files\7-Zip"?
What are the permissions on this folder? Please share the icacls output.
icacls "C:\Program Files"
Or
icacls "C:\Program Files\SomeSubFolder"
As I tried to explain in your first question, by default it's a matter of permissions, users have read, administrators have full. We forum users do not know if you or some app on your pc has changed permissions. We do not know if the process you are running has UAC elevation or not.
You also commented about moving a file from a mapped drive. Does the problem also occur when moving a file from a different folder on the C drive?
By default the explorer should not be elevated. Open 2 command prompts, one with "run as administrator", and one without admin rights. Try a copy command in both windows. Use a source file on the C drive. What results do you get?