Some ideas:
1) Inserting a table creates this behavior (you can format the table to look like its just an ordinary range). I'm not really familiar with tables though - not sure of all the ins and outs.
2) Locking all cells to the right of G and protecting the sheet
3) User can select A-G and then key-enter data (this is up the the user though - the cursor stays in the selected area as long as you don't mouse out of it).
4) In code use the Scroll Area: Worksheets("Sheet1").ScrollArea = "A1:G100"
I'm also not real familiar with using a worksheet ScrollArea - so I'm not sure if it has a "native" counterpart in the Excel interface (I couldn't find one just now ... )
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