Identify duplicates across 2-x column combinations

pls try this

Hi Dominik82 ,

Ahmedx ,good answer!
And you can also use EARILER in the DAX:
Use these DAX to create new columns:

Start + Employee = 
IF(
    COUNTROWS(
        FILTER(
            'Sheet23',
            'Sheet23'[StartTimeDate] = EARLIER(Sheet23[StartTimeDate]) && 
            'Sheet23'[Employee] = EARLIER(Sheet23[Employee])
            )
    ) > 1,
    1,
    BLANK()
)

Start + End + Employee = 
IF(
    COUNTROWS(
        FILTER(
            'Sheet23',
            'Sheet23'[StartTimeDate] = EARLIER(Sheet23[StartTimeDate]) && 
            'Sheet23'[EndTimeDate] = EARLIER(Sheet23[EndTimeDate]) &&
            'Sheet23'[Employee] = EARLIER(Sheet23[Employee])
        )

    ) > 1,
    1,
    BLANK()
)

The final output is as below:

Best Regards,
Dino Tao
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