Load file error to Matlab

[maxwell10]

Hi

I want to load 4 .asc files but one of the file didn't load, it print an error:

Number of columns on line 4891 of ASCII file FlowWater_3.asc must be the same as previous lines.

I was advice to look at line 4891 of the file FlowWater_3.asc and modify it so it contains the same number of columns as the previous lines.

How can I open this heavy file (125MB) and count 4891 rows?