Is it possible to open multiple worksheets in a hidden instance of
Excel and copy worksheets to a workbook in the original visible
instance? I want to open multiple files and would prefer to not see
all the files being opened in the windows task bar?

wb was opened in a hidden instance of excel. An error occurs at the
ws.copy line.

The error is: "Method 'Copy' of object '_Worksheet' failed"

Is there another option avoid seeing the files being opened in the
task bar?

application.screenupdating = false

Set wb1 = ActiveWorkbook

Set wb = xlApp.Workbooks.Open(fs.FoundFiles.Item(i))

For Each ws In wb.Worksheets
ws.Copy befo=wb1.Sheets(wb1.Sheets.Count)
Next ws

application.screenupdating = true

I am using XP sp3 with Excel 2003

I have it working by inserting worksheets and copying the usedrange.
I would prefer to copy the whole worksheet.