None of those should be interfering with CF. However, you can check that
by opening the file with macros disabled.

Since it works in a new sheet, are you sure you're meeting the condition
(i.e., that E4 contains "Y" with no leading or trailing spaces)?

In article ,
Jock wrote:

1 to colour rows depending on what number is placed in cells in 'C',
2 to open a Word doc, and
3 to sort the sheet by ascending number on column 'C'.
Could any of these codes be stopping the conditional formatting working?