Please inspect the Source table script produced by both versions of JMP when you open the file. Are there any differences?
Example:
//JMP 16.2.0
    Open(
    "$DESKTOP/test.csv",
    columns(
        New Column( "Col 1", Character, "Nominal" ),
        New Column( "Col 2", Character, "Nominal" )
    ),
    Import Settings(
        End Of Line( CRLF, CR, LF ),
        End Of Field( Comma, CSV( 1 ) ),
        Strip Quotes( 0 ),
        Use Apostrophe as Quotation Mark( 0 ),
        Use Regional Settings( 0 ),
        Scan Whole File( 1 ),
        Treat empty columns as numeric( 0 ),
        CompressNumericColumns( 0 ),
        CompressCharacterColumns( 0 ),
        CompressAllowListCheck( 0 ),
        Labels( 1 ),
        Column Names Start( 1 ),
        Data Starts( 2 ),
        Lines To Read( "All" ),
        Year Rule( "20xx" )
    )
)
//JMP 17.0.0
Open(
    "$DESKTOP/test.csv",
    columns(
        New Column( "Col 1", Character, "Nominal" ),
        New Column( "Col 2", Character, "Nominal" )
    ),
    Import Settings(
        End Of Line( CRLF, CR, LF ),
        End Of Field( Comma, CSV( 1 ) ),
        Strip Quotes( 0 ),
        Use Apostrophe as Quotation Mark( 0 ),
        Use Regional Settings( 0 ),
        Scan Whole File( 0 ),
        Treat empty columns as numeric( 0 ),
        CompressNumericColumns( 0 ),
        CompressCharacterColumns( 0 ),
        CompressAllowListCheck( 0 ),
        Labels( 1 ),
        Column Names Start( 1 ),
        First Named Column( 1 ),
        Data Starts( 2 ),
        Lines To Read( "All" ),
        Year Rule( "20xx" )
    )
)
					
				
			
			
				
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