The line you have edited is a comment, not a directive. The PHP.ini file has a lot of information to help you out, most of it is only for you to read and not the computer.
You need to make sure that the following lines are not commented (have no
; at the beginning of the line) and have the correct values:
display_errors = On
html_errors = On
error_reporting = E_ALL
They will not necessarily be present and commented. On my system, for example, the
display_errors line looked like this:
display_errors = Off
What you uncommented was a line explaining some of the PHP.ini options. It is there to explain to human users how to configure the file. Normal options have the format (note the
option_name = option_value
As you can see, the line you edited does not have that format. The equivalent line on my system looks like this:
; E_ALL - All errors and warnings (includes E_STRICT as of PHP 5.4.0)
Uncommenting that line will not help. In fact, I am surprised that PHP would work at all with it uncommented.