Usually you get these kind of errors when loading a VB project from someone
else's machine. This usually means that a control (ocx) may not be on the
users machine.

What does the error message state exactly? Is it prompting you that it needs
to be configured or ??? and then takes you through the Office Excel
configuration asking you for the Excel CD, maybe?

What controls/references are in your workbook? VB controls added through
references in the VBA Editor?