Thank you all. @karolus
This worked for me. It was one column out but changing +3 to +2 seemed to fix that.
To answer your question " For which reason do you need this magic Columnletter?", well it was to be part of a bigger formula.
What I am trying to ultimately do is have many sheets that are almost the same but be able to fill many rows in the first sheet from other sheets. Someone should be able to write the name of a sheet eg “Sheet3” in one cell and it fills the cells under it with the cells from “Sheet3”.
Sheet1:
C3 = Editable cell that people can write the name of another sheet, eg. “Sheet3”.
C4 = Editable cell that people can write some text, eg. “Text1”, that is the the header of a table in sheet “Sheet3” found within a range “D4:Y4” .
C6 = Returned value from “Sheet3” column “Text1”, same row as this row, Row().
Sheet3:
X4 = Text1 Y4 = Text2
X6 = SomeValue X6 = OtherValue
I am almost there thanks to your help, I just need now the bold part of this formula altered for Sheet1 C6.
=INDIRECT(C$3 & CONCATENATE(".",SUBSTITUTE(ADDRESS(1,MATCH(C$4,D4:Y4,0)+2,4),“1”,""),ROW()))
The bold section just needs to look in the user written sheet eg. Sheet3.D4:Y4