Hello Old Bob,
This means that the Excel-file itself is password protected by Excel. This has nothing to do with AxCrypt. Google the error message, and the top hit is: https://support.microsoft.com/en-in/help/321147/error-message-the-password-you-supplied-is-not-correct .
Apparently, you have both password-protected the Excel file and also then encrypted it with AxCrypt. You’ll have to remember the Excel password – or get a cracker. Contrary to AxCrypt, Excel password protection can usually be cracked ;-)