CS0433 System.Web.Extensions Error - VS2005 and VS2008 side by side
CS0433 System.Web.Extensions Error - VS2005 and VS2008 side by side
so you get something like this:
Compiler Error Message: CS0433: The type 'System.Web.UI.ScriptManager' exists in both 'c:\WINDOWS\assembly\GAC_MSIL\System.Web.Extensions\1.0.61025.0__31bf3856ad364e35\System.Web.Extensions.dll' and 'c:\WINDOWS\assembly\GAC_MSIL\System.Web.Extensions\3.5.0.0__31bf3856ad364e35\System.Web.Extensions.dll'
OR
'System.Web.UI.ScriptManager' exists in both 'c:\WINDOWS\assembly\GAC_MSIL\System.Web.Extensions\1.0.61025.0__31bf3856ad364e35\System.Web.Extensions.dll' and 'c:\WINDOWS\assembly\GAC_MSIL\System.Web.Extensions\3.5.0.0__31bf3856ad364e35\System.Web.Extensions.dll'
Solution:
Check if you have in the web.config
<add assembly="
System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"
/> CHANGE IT TO:
<add assembly="
System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
/>
also, look for (in the page):
<%@ Register Assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral,
PublicKeyToken=31bf3856ad364e35" Namespace="System.Web.UI" TagPrefix="asp" %>
REMOVE IT !
try it, it should work now
BTW - this problem occurs even in VS2008 when there's a VS2005 with AJAX 1.0 on the same machine !