I got this from Excel help, so I will get them the credit, even if it isnt the answer...
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To enable people to work with the data on your Web page in a browser, you can make your data interactive. For example, you can publish an interactive spreadsheet that calculates loan information. A user who browses to the page can enter financial information such as loan amount and interest rate to calculate a monthly payment.
Select the Add interactivity with check box and select the type of interactivity you want from the list. The type of interactivity that's available depends on what you are publishing. For example:
For a worksheet that contains formulas, select Spreadsheet functionality so that users of your Web page can enter new values in a cell and the formulas will automatically calculate the results.
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My thought is that the spreadsheets are not enabled for interactivity, and that is preventing users from working with them. I could be wrong. Do you have any toolbars loaded? IE the standard formatting toolbar, is it loaded on the webpage? That may be something. You may need to specify that onload, the toolbars have a property of show or visible set to them....
Here is something else, I found that you might jsut have the web bar showing, which means you simply need to click the buuton on that bar, which should show the rest...
Show only Web toolbar buttons
If the Web toolbar is not displayed, point to Toolbars on the View menu, and then click Web.
On the Web toolbar, click Show Only Web Toolbar .
Tip
To show the toolbars that are hidden, click Show Only Web Toolbar again.
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Look this up in the excel help, so that you can see the picture of the button: it looks like a square with a green arrow pointing up to 2 lines in it. This will show the other toolbars. I tried it out in excel. It just depends on if this is the problem you are having. Let us know if this is not it.