Formula does not work if cell reference is not included

I have an Excel file that contains two spreadsheets, PM Coord. and Section. The I6 cell of the Section spreadsheet contains a formula (see below) that references E6:J6 of PM Coord. spreadsheet. This formula works in cells J6, H6, G6, etc of the Section spreadsheet, but I can't get this same formula to work in the M6, K6, L6, N6, etc. cells of the Section spreadsheet, unless the formula contains those column references. For example, I was able to get the formula to work in cell M6 of the Section spreadsheet by changing the cell reference to 'PM Coord.'!E6:M6, which also worked in cell L6, K6, J6, etc. or L7, K7, J7, M7, etc. I have also checked the format, it is set to General, so that is not the solution. Does anyone know what there has to be a reference to that column in the formula before it will work? This is very wierd.

=IF('PM Coord.'!E6:J6=""," ",'PM Coord.'!J6)

Thank you for your immediate reply.

I pressed F2, then CTRL+SHIFT+ENTER and the formula works. Thank you so much.

@ yreddic

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