RsAccessDeniedToSecureData

I've installed a fresh load of SQL Server 2005 onto a Windows 2000 server, including all the trimmings with SS2005.

Reporting Services 2005 is the main thing I want to initially check out, but I can't get it to work.

In the 'Reporting Services Configuration' it shows the 'Web Service Identity' as a blank grey box which can not be edited. I can't help but think this might be where the issue is.

I looked at this thread, as it describes the exact same problem, but the solution did not work for me.

The RS service will start up, but then when I navigate to http://localhost/reportserver or http://localhost/reports it gives me the following error:
Reporting Services Error


The Report Server Web Service is unable to access secure information in the
report server. Please verify that the WebServiceAccount is specified correctly
in the report server config file. (rsAccessDeniedToSecureData) I have tried various items suggested in another thread...
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=58665&SiteID=1

but none to any avail.

rsreportservices.config has no entry in
<WebServiceAccount></WebServiceAccount>

Can anyone offer me any advice with this?

Thanks,
HN