Run Button disappears for SOME .m scripts

When ex8.m is selected, the 'Run' button does not appear. When ex8_cofi.m is selected, the 'Run' button is there. See attached screenshots.

I went to the Command Window and ran ex8.m "manually". It appeared to succeed, but now the 'Run' button disappeared for ex8_cofi.m as well!

[Walter Roberson]

In the first of those, you have at least warnings, as indicated by the orange color to the upper right of the area. The second of those shows green, indicating no warnings or errors. Possibly you need to fix the warnings.

I would also suggest experimenting with commenting out the

clear all; close all; clc

as "clear all" does a lot more than you might expect, and might be interferring with the parsing of the script.