Pedro,
It's hard to assess what exactly you're struggling with, it would help to have more detail.
In my experience it's always better to prepare upload files within excel and to let the WS scripts do their magic on the fully prepared worksheets. So that there is no need for WS to execute Excel functionalities even though it can.
Checking for duplicates and deleting rows seems perfect for a little VBA scripting on the Excelsheet while preparing the file for upload.
hth, Jan
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jan ketele
Xeikon Manufacturing NV
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