@htlcnn, sometimes something goes wrong with Excel. Have a look at the known issues here:
Excel nodes can be rendered non-functional by bad registry data. To correct this: Go to Start–> Run → regedit. Browse to HKEY_CLASSES_ROOT–>TypeLib–>{00020813-0000-0000-C000-000000000046}. Delete the 1.8 key.
We recommend using Excel 2013 or higher. Excel 2010 works in most cases, but 2007 does not.
You can also dive into this thread, maybe, it’ll help you: Excel Nodes Fail Dynamo 1.1.0