I'm trying to plot a series of X Y coordinates found in an excel spreadsheet as points on my map. I'm able to successfully add the spreadsheet to my table of contents but when I right click the file and then click 'Display X Y Data,' the next dialogue box that appears doesn't allow me to select the columns in the excel sheet which contain my X Y coordinates as the "X field" and "Y field." As a matter of fact, when I click the drop down arrows next to X Field and Y Field, none of the column headers from my excel sheet are available. The column headers where my X Y coordinates are only contain letters and underscores and meet all the other criteria to be readable by ArcMap.
Is there some step that I am missing?