Conditional formatting to higlightvduplicate values, excluding blank rows.

Hi AlessiaZak - You can modify the DAX measure to exclude rows where the Customer value is null. This will ensure that null values are not counted or highlighted as duplicates.

The NOT ISBLANK ( 'Table'[Customer] ) condition ensures that the measure only evaluates non-null customer values.
The condition 'Table'[Customer] <> BLANK() inside the CALCULATETABLE function excludes null values from being counted as duplicates.

Rowcount =
IF (
NOT ISBLANK ( 'Table'[Customer] ) &&
COUNTROWS (
CALCULATETABLE (
'Table',
ALLSELECTED ( 'Table' ),
'Table'[Customer] <> BLANK()
)
) = 1,
0,
1
)

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