Can't select column name when doing a measure

[JohnphamQT]

I'm not able to do pick a column name when doing a measurement and it greys out suggesting that i'm not able to use it. 
My formula is = 

events in progress =
CALCULATE(
COUNTROWS('public 10-bookgirl';
FILTER('public 10-bookgirl'[start 2]; <= MAX('Date Range'[DateTime]));
FILTER('public 10-bookgirl'[end 2] = BLANK() || ('public 10-bookgirl'[end 2] > MAX( 'Date Range'[DateTime]))

)

start 2 and end 2 is showing up grey even though it is the correct column name please advise.

[MFelix · Accepted solution]

Hi @JohnphamQT,

When using filter the first parameter is the table or column wher you wan to use the filter then you must refer to the specific column filter on the second parameter change your measure to

Events in progress =
CALCULATE (
COUNTROWS ( 'public 10-bookgirl' );
FILTER (
ALL ( 'public 10-bookgirl'[start 2] );
'public 10-bookgirl'[start 2] <= MAX ( 'Date Range'[DateTime] )
);
FILTER (
ALL ( 'public 10-bookgirl'[end 2] );
'public 10-bookgirl'[end 2] = BLANK ()
|| 'public 10-bookgirl'[end 2] > MAX ( 'Date Range'[DateTime] )
)
)

This should work.

Regards,
MFelix