Hello i think you disabled auto calculation.
So you have to enable it doing this
TOOLS | OPTIONS | CALCULATION and select AUTOMATIC.
But be careful if your sheets contain huge formulas.

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M.A.
"Tony" wrote in message ...

I got few worksheets in a workbook. Each worksheet has it name. I try to
write a formula to extra the worksheet name into a cell. The formula is "
=RIGHT(CELL("filename"),4) " . It works, however, if I change worksheet from
one to another one. This formula doesn't change (calculate) itself. I have
to re-calcuate by press "F9", sometime I forgot to re-calculate before I
prite out the report. It got the wrong worksheet name. Can anyone help me
to improve my formula and make it works automatically. Thank you very much.