Excel 2000 to 2003 - Use Excel's main menu select View>Toolbars and check that XLC Tools is selected. If XLC tools does not appear in the list of toolbars then it is not installed.
Excel 2007 to 2010 - The XLC toolbar appears on the ribbon under the "Add-Ins" tab. If it is not visible then XLC has not been installed.
Common installation problems:
- Administrator access is required for installation.
- Check your "User Account Settings" (go to the control panel and select User Accounts).
- The README.TXT file delivered with the XLC zip file download includes instructions for manual configuration and can be useful for debugging installation problems.