Clicked on Link, GCP table opened. Had this error, message
" 5 appears to contain invalid data. Please resolve before continuing."
Selected the Auto Fix and the message was
“Suggested changes by Autofix displayed above. Changes made: Performed basic formatting. Everything looks good now, please click Save after reviewing the changes.”
After selecting Save we get message;
“5 appears to contain invalid data. Please resolve before continuing.”
Your using the wrong EPSG number for that area. I had this happen to me a few weeks ago and then I was told I we used this number versus that number, then magic happened and it worked.
There can be several EPSG Codes for your area and you have to determine which one it is, especially if your close to the edge of two EPSG zones.