how do I produce an error dialogue box in VBA

[caltrin]

e.g.

when the value of cell D10 becomes higher than 100 %

Excel should display a error message box saying something like


Correction Total Too High ! Please Check

 

[jimboy]

Right mouse over the sheet name (i.e. Sheet1) and select view code, then paste this in, it will run when a change in the sheet is made;

Private Sub Worksheet_Change(ByVal Target As Range)
If Range("D10").Value > 1 Then
If MsgBox("Correction Total Too High ! Please Check", vbOKOnly, "See range D10") = vbOK Then:
End If
End Sub

 

[Joe4]

Or just use Validation, found under the Data drop down box. This allows you to specify the conditions of the values entered into the specific cells, and allows you to return an error message for incorrect values.

Edit: Validation will only work if a hard coded value is being typed into the cell. If it is a formula, link, or is pasted into the cell, use the code jimboy provided.