I have a series of manipulations in VBA.
I need to run this on data which is in ms-excel files I receive daily.
These files have multiple sheets (of different names) but the VBA applies to
them all the same.

How can I have the VBA access the cells in another ms-excel file?

I tried for example:
Worksheets(SheetName).Rows(1).Cells(1).Value

where I'd haveopen both teh xls files (one with data and the other with the
code),
and set the SheetName to the name of the target sheet.

But I get a "subscript out of range" error, which probably means the
sheetName was not found.

What is the best way of reading or accessing data on other xls sheets ?

Thanks in adv.
Tim