How to View Details of SharePoint unknown errors

Turn: http://www.cnblogs.com/carysun/archive/2010/01/07/sharepoint-unknownerror.html"

The content of this article is from the Internet, but this is required by every SharePoint developer. When developing and debugging A SharePoint application, if yourProgramError: the error page of SharePoint only displays the "Unknown error" prompt, which is inconvenient to view.

You can view the error information directly on the error page using the following method. Modify the Web. config file in the root directory of the Web application:
1. maxcontrols = "200" callstack ="False"Maxcontrols =" 200 "callstack ="True"
Ii. customerrors mode ="On"Changed to customerrors mode ="Off"