When installing DBXL on servers with SharePoint 2007 or servers which have any special .config entries you may get the following error in the Qdabra Error Log.

Event Type: Error
Event Source: Database Accelerator
Event Category: None
Event ID: 2000
Description: Error initializing DBXL database. Client found response content type of 'text/html; charset=utf-8', but expected 'text/xml'. The request failed with the error message: -- The file you are attempting to save or retrieve has been blocked from this Web site by the server administrators.

One of the possible reasons for this was covered in a previous blog post. That blog post also provided a solution for the issue. Another possible solution follows.

Locate the web.config file located in the QdabraWebService directory, and open it with Notepad. Find the <httpModules> tags and replace its contents with the following three lines:

<httpModules>
    <clear />
    <add name="OutputCache"   type="System.Web.Caching.OutputCacheModule"/>
    <add name="WindowsAuthentication" type="System.Web.Security.WindowsAuthenticationModule"/>
</httpModules>

This is to clear the entries from the root folder and add the essential modules needed for DBXL for the webservice to function.