Insert Data into closed workbook and autofill formulas.

[Macro_Nerd99]

I'm trying to transfer data from one workbook to another and autofill columns with formulas in them without having to open the destination workbook.
Is that possible?

Here's what I'm trying to accomplish:
- copy columns 1-3 of used data from activeworksheet and paste into columns 1-3 in Sheet4 of destination workbook(in the next available row).
- autofill column 4 with Environ$("username") in new rows of destination workbook.
- autofill formulas in columns E:H to end of data.

What do you recommend?
Thanks