|Here's the thing. Just using the 'administrator' account isn't enough in and of itself. The administrator account on all PC's must use the exact same password in order to avoid the credential request.|
So, if the password on the remote system was different, even if it was the same 'administrator' account, you'd get asked to login to the share.
Other than that, I don't know what to tell you. If it was working and then stopped after you used gpedit, then you know it was something you did at that point that caused the change. In that case, only you know what you did, and only you can undo it.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.