Question: `DataServiceRequestException` was unhandled by user code. An error occurred while processing this request.

This is in relation to the previous post I added 

```
public void AddEmailAddress(EmailAddressEntity emailAddressTobeAdded)
{
    AddObject("EmailAddress", emailAddressTobeAdded);
    SaveChanges();
}

```

Again the code breaks and gives a new exception this time. Last time it was Storage Client Exception, now it is `DataServiceRequestException`. Code breaks at `SaveChanges`.

Answer: 
It sounds like JOD Converter is precisely what you need since you're looking at multi format conversions from Java. You would install OpenOffice on your server and link it up with JOD Converter. When a document is uploaded, your application would call JOD Converter to perform the conversion and stream the converted document back to the caller. Alternatively you can put the file somewhere, and send a link (URL) back to the caller so they can fetch the document. You can also look at [JOD Reports](http://jodreports.sourceforge.net/) or [Docmosis](http://www.docmosis.com) if you need to manipulate the documents.
GWT is mostly a client side toolkit. Are you trying to make a tool that does all the conversion on the client side, with no help from the server? In that case, you should be looking for JavaScript libraries that can read/convert all those formats. If you are planning to have the user upload their files to the server, then you can use whatever technology you want on the server, and just use GWT for the UI.