Import/Export Tool Cannot send session cache limiter

I have installed the Import/Export tool and followed all instructions to download the format of the product database. I tried importing the database with product info and I get the following as an error:

Uploaded spreadsheet file has validation errors!
See also 'System > Error Logs' for more details.
No server data has been changed.

In the error log it says: Export/Import: Invalid header in the Products worksheet

Note: this is a new install of OpenCart and I am a first time user. I inputted the data into the downloaded exported product file.

Thanks!