I create a xls in 2003. It worked great!

We are now migrating to 2007, On my PC (once again) everything run smoothly.
But when others run it they get errors left right and center! I started
stepping through my code to try to resolve the problem(s) but am now more
confused then ever. For instance, I use the code below to delete a worksheet

Dim DstWkb As Workbook
Dim DstWks As String

Set DstWkb = ThisWorkbook
DstWks = "Project Info"

DstWkb.Worksheets(DstWks).Delete

and it generates an err.number = 9??? and yet it does delete the worksheet?!
Why does it work without issue for me and yet generate errors for others,
even though it works fine even for them (just reports errors)?

Thank you for your guidance,

QB