I have a solution for checking if an Excel worksheet exists or not. This can come in handy if you are creating a new sheet based on a dataset. You check for the new sheet and if the sheet exists you can alter the old sheet if the sheet does not exist then you can create a new sheet.
Where Excel cell [A1] contains the name of the sheet you are checking for.
Now if this procedure was part of a loop you may wish to check all of the cells from say A1 to the last used row in column A. Then the following might be more relevant.
Dim i as integer
For i = 2 To Range("A" & Rows.Count).End(xlUp).Row
If Not Evaluate("ISREF('" & range("A" & i) & "'!A1)") Then
' Your code
End If Next i
The procedure is very useful for procedures where you may wish to create a new sheet if it does not already exist.