I have about 10 ASCII files from the same governmental source imported to my ArcMap project. Half of the files came in with a defined coordinate system and projected fine. The other half have an undefined coordinate system and I cannot figure out how to define them. I have checked permissions and I have write permissions for all. The metadata tells me the file has a datum of NAD 1983 and a Transverse Mercator projection. I have tried defining the projection as a multitude of various coordinate systems to no avail. I keep getting this box...
What am I doing wrong?!
