Office Web Components are a set of Active-X components that work in conjunction with XML coding on web pages to provide an impressive interactive spreadsheet capability. Unless you know for certain that the OWC components are installed on your machine (the file might be on the computer but not installed), you might try going to the Microsoft webpage and download and install the OWCs. A couple people have written in the past with a similar problem and this has solved it.
Also, it is my understanding that the OWCs only works with Internet Explorer v5.5 and later; I have never tested them with Netscape or other browsers to see if they will work. I did some research on OWC requirements and determined that ActiveX must be enabled in order for OWC to work. I tested it by disabling ActiveX in the Internet Security setting for Internet Explorer, and indeed they stopped working and I got a notice that OWC components were not installed. Re-enabling the ActiveX got them working again.
This can present a problem for people who either intentionally or unintentionally have the ActiveX control setting disabled for security reasons. Some firewalls will disable ActiveX by default. So, if you consider it to be worth the effort, I suggest going to the Tools->Internet Options... menu and then selecting the Security tab. From there, click on Custom Level and scroll down to "Run ActiveX controls and plug-ins" and select Enable. Hopefully that will work. If it does and you don't want to leave the setting there, you might consider the Prompt option.
A couple sample screen shots of what you are missing are included below. Many more calculators will be provided in the future. As is typical of Microsoft, they require that you own an Office 2002 (XP) product to receive the license for OWC. The least expensive method is to upgrade only your current version of Excel (<$100). Download the OWC from Microsoft by clicking here.
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