Hi Chris,

Yes, it is possible to add only vertical error bars to a single data point in a series on a scatter chart in Excel 2007. Here are the steps to do so:

1. Select the data point to which you want to add the vertical error bars.
2. Right-click on the data point and select "Format Data Point" from the drop-down menu.
3. In the "Format Data Point" dialog box, click on the "Error Bars" tab.
4. Under "Error Amount", select "Custom" and then click on the "Specify Value" button.
5. In the "Custom Error Bars" dialog box, select "Vertical Error Bars" under "Error Amount".
6. In the "Positive Error Value" box, enter the value for the size of the error bar.
7. Leave the "Negative Error Value" box blank.
8. Click "OK" to close the "Custom Error Bars" dialog box.
9. Click "OK" to close the "Format Data Point" dialog box.

That's it! You have now added only vertical error bars to a single data point in a series on a scatter chart in Excel 2007.