Rename the sde connection file to start with an alpabet. Also could you copy the SDE file to a shorter, non-OneDrive path with no space or special characters in pathname.
@JayantaPoddar Hi again, I have tried everything and still get this message. Does anyone else had this problem before? Thanks
@JayantaPoddar Thank you for your message. I have tried it and it still doesn't work.
I'm having this issue as well... Has anyone found a resolution?