1, Save a backup before doing anything.
2, From Excel save your products as a csv or tab delimited text file.
3, Open Product Control and select File / Import Products (Older Versions).
4, Check the CSV Format box for a csv format.
5, Use the Open button to select your text file.
6, In step 3 scan the file to see if the fields line up. Click on the right "Field" column to align the fields to match your import order.
7, Step for use the Import button.