Symptoms
When attempting to open a site running version 7 or later, the following error is thrown:
Server Error in '/ASPDNSF/Web' Application.
--------------------------------------------------------------------------------
Configuration Error
Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.
Parser Error Message: Could not load file or assembly 'Microsoft.Web.Services3, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.
Cause
This is caused by a reference to Microsoft WSE3.0 components in the web.config file.
Solution
To fix this, either install the MS WSE3.0 addon (available for free from Microsoft's site) or edit the web.config file to remove the reference, which is not required for normal operation:
1 - Open the web.config file in the root of your site
2 - Find the following line and comment it out:
<add assembly="Microsoft.Web.Services3, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
3 - Save and close the web.config file and try again