A hyperlink does not work in an Excel 2007 client workbook that is published to Excel Services in SharePoint Server 2007
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When you create a hyperlink in a Microsoft Office Excel 2007 client workbook that is published to Excel Services in Microsoft Office SharePoint Server 2007, the hyperlink does not work. This behavior occurs when you try to click the hyperlink by using the Excel Web Access Web Part.
This behavior occurs because Excel Services does not support relative hyperlinks. When the base address of the hyperlink is the base path of the SharePoint Server 2007 server in which the workbook is published, Excel 2007 converts the absolute path into a relative path. The relative path is based on the base path of the server.
To work around this behavior, configure Excel 2007 so that it does not update links when the workbook is saved. To do this, follow these steps:
In Excel 2007, click the Microsoft Office Button, click Excel Options, and then click Advanced.
Under General, click Web Options.
On the Files tab, click to clear the Update links on save check box.