I get an error message when trying to view a 7mb Excel document using "view asweb page" in OWA 2007.The document cannot be converted by the WebReady Document Viewing service because it is larger than the maximum size limit set by the administrator for your organization.How do I change the setting?

The Limit is 5MB and you can change this in the registry HKLM\System\CCS\Services\MSExchange OWA\WebReadyDocumentViewing DWORD: MaxDocumentInputSize The WebReadyDocumentViewing key does not exist.Enter 10000 to set to 10mb andrestarted the World Wide Web Publishing Service Deli

Great answer!! Now I have a new issue. "This document is taking too long to convert to be viewed as a Web page. The file may be too large." Any Ideas? It is a 7mb multi tabed excel spreadsheet.

This might be a timeout issue. Try to change the UserContextTimeoutvalue on the Client Access Server http://technet.microsoft.com/en-us/library/bb123515.aspx