You see this message when attempting to run your application:
Server Error in ‘XXX’ Application.
Parser Error
Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately.
Parser Error Message: Unknown server tag ‘asp:ScriptManager’.
This error occurs when you overwrite your application’s Web.config file with an older version that does not contain the appropriate information to enable Ajax functionality in your application.
Step 1: Make a copy of your application’s Web.config file.
Step 2: Create a new application using Iron Speed Designer V4.2 or later. This will create a good Web.config file.
Step 3: Copy the Web.config file from the new application folder into your application folder, overwriting the older or mis-configured Web.config file.
Step 4: Apply any necessary changes to the new Web.config file that may be present in your older Web.config file (from the backup copy).
Part VII: Troubleshooting Applications
Application Runs But No Data is Displayed