MS Excel won't open the file that I save using the Save Graph Data button

[PGriffith]

And what version of Ignition are you using? There's a bug in 7.9.8 that's fixed in 7.9.9:

Export to excel 7.9.8

As a heads up - there is another regression we noticed related to the fix for the ‘nullsEmpty’ parameter that causes the Easy Chart’s data export to be blank. That fix, and consistent behavior for exportExcel (with or without a sequence of datasets, with and without a nullsEmpty argument) should go into 7.9.9.