In an excel project show error value# , so how to find error or what way to find it?

=IFERROR(A1;"Error")

Microsoft Excel may display the #VALUE! error if your formula includes cells that contain different data types.............................

http://office.microsoft.com/en-ca/excel-help/correct-a-value-error-HP.aspx

Excel can display the #VALUE! error if your formula includes cells that contain different data types. If smart tags are turned on and you position the mouse pointer over the smart tag, the ScreenTip displays "A value used in the formula is of the wrong data type." You can typically fix this problem by making minor changes to your formula.

same advise as MR.Atif Tanveer

SORRY TO ALL BUT MY Q:- IS  IF IN MS EXCEL SHOW VALUE ERROR SO WE HOW FIND IT. OR WHERE IS MISTAKE TO ARRRANGE IT RIGHT. 

simply we go to Menu

"TOOLS__Fourmula Auditing___Evaluate Fourmula"______

then show one dialog,"evaluate formula", then click "Evaluate", then "step in" and "close" dialoge and go up near error . if have any objection do try this one and vote my Q:- thanks

Just check, if it work try to use the error checking option, its available in the formula tab, formula auditing,