it is possible when one of the following factor gets changed:
1. data source;
2. variable (i.e. Var_FileName = c:\folderA\PackageC\SalesFor2011Dec.xls, now it IS c:\folderK\PackageH\SalesFor2012Jan.xls);
3. file location or file name (i.e. as #2 above);
4. data sheet range;
5. Title name;
6. updates...