Hi Josy,

I'm sorry to hear that you accidentally deleted all the sheets in your Excel 2007 workbook. Fortunately, there is a way to recover the deleted sheets. Here's how:

1. Open the Excel workbook that you deleted the sheets from.
2. Click on the "Office" button in the top left corner of the screen.
3. Click on "Open" and then select "Recent Documents".
4. Scroll down to the bottom of the list and click on "Recover Unsaved Workbooks".
5. Look for the workbook that you deleted the sheets from and click on it to open it.
6. Once the workbook is open, you should see a message at the top of the screen that says "Document Recovery". Click on it.
7. In the Document Recovery pane, you should see a list of all the sheets that were deleted. Select the sheets that you want to recover.
8. Click on the "Save As" button in the top left corner of the screen and save the recovered sheets as a new workbook.

That's it! Your deleted sheets should now be recovered and saved in a new workbook.