References damaged after save


Attached xlsx file is very simple. in Sheet1 there are two values (cell A2 = 1, cell A3 = 1). In Sheet2 there is a sum of referenced values ("=SUM(Sheet1!A2:Sheet1:A3"). After update via EPPlus, I have to read this xlsx using standard ADO.NET (OleDbConnection). after updating A2 and/or A3 in Sheet1, I get always "1" in Sheet2 sum. which is wrong. If I open this workbook in Excel, value of sum is correct, but - even if I don't change anything - Excel still insist on resaving this file (probably because knowing sum is outdated/invalid, it updated correct sum on load).

Is there any way to force full calculations (including formulas containing references to another worksheet) before save?


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