Changing font size of one cell in excel using C#
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I am working on a project that writes data to an excel file. 
Everything is finished now, however I need a few cells with a bigger size than the rest (title etc). 

I have read about this about the internet, but I keep having the same problem: when I execute my code (see below what i've tried), everything in the worksheet becomes larger. 

What I already've tried:

worksheet.Rows[1].Cells[7].Style.Font.Size = 20; 

worksheet.get_Range("A7", "A7").Style.Font.Size = 20;

none of this seems to work..

Anybody can help? 

