Need to DownGrade to ASP .NET 3.0 in Visual Studio 2008

Posted on 2008-11-18
Last Modified: 2013-11-26

I am developing my own .aspx pages using Visual Studio 2008.  Much to my chagrin, these will not work on my web-host because they do not support .NET 3.5 on their Windows Server.  

They do; however, support .NET 3.0  (at least so they say).  

What is the easiest way in Visual Studio 2008 to change an existing project (which apparently defaults to .NET 3.5 )  to use the .NET 3.0 framework instead?  

(What are the main differences or gotchyas between 3.0 and 3.5 ?? )

Question by:LindyGeek
    LVL 53

    Expert Comment

    NET framework 3.0:

    This framework is the key for developing application under Vista.
    It is just a set of assembly which use XML to map:

    Communication (WCF)
    View (WPF)
    Workflow (WWF)
    Digital identity (CardSpace)
    The framework is still the .NET framework2.0 behind it.
    For a lot of developer this is not a real framework.

    .NET framework 3.5:

    It implement Linq evolution in language. So we have the folowing evolution in class:

    Linq for SQL, XML, Dataset, Object
    Addin system
    p2p base class
    Active directory
    ASP.NET Ajax
    LVL 53

    Expert Comment

    .Net 3.0  = .net 2.0 features + WF+WPF+WCF+ Cardspace

    .Net 3.5 = .Net 3.0 features + LINQ, ASP.NET AJAX, new controls, richer WCF support, and a few other features that aren't in .NET 3.0.

    Also u can refer the link for more info

    Author Comment

    Thanks for the description.  Very Helpful to this newbie.  

    Can you (or someone else) walk me through what I need to do from the Visual Studio 2008 Environment in order to make it so when I upload my files to my website provider, the website will use .NET 3.0 ?  

    I ask this because currently it won't even run it.  

    I get:  

    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: Child nodes not allowed.

    Source Error:

    Line 78:             <compilers>
    Line 79:                   <compiler language="c#;cs;csharp" extension=".cs" warningLevel="4" type="Microsoft.CSharp.CSharpCodeProvider, System, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    Line 80:                         <providerOption name="CompilerVersion" value="v3.5"/>
    Line 81:                         <providerOption name="WarnAsError" value="false"/>
    Line 82:                   </compiler>

    Source File: \\nawinfs05\home\users\web\b446\ipw.integralnest\web.config    Line: 80

    Version Information: Microsoft .NET Framework Version:2.0.50727.832; ASP.NET Version:2.0.50727.832

    Author Comment

    I am told this happens because I have .NET 3.5 set up (the Visual Studio 2008 default) and I need to make it .NET 3.0.  I do not know how to do this from Visual Studio.

    Thank You.  

    Author Comment

    I am looking for Step-By-Step instruction for Dummies in Visual Studio 2008.  
    like ...

    "In order to take a project from .NET 3.5 to .NET 3.0 ...

    -"  Go to menu / file "X"
    - Go to the "Y" Tab
    - Select "B" and
    - type in "joebama"
    - fix any compilation errors that occur from the transfer

    Much Appreciation.  

    LVL 2

    Accepted Solution

    According to MSDN and the error you are getting, you can't have any child elements in the <compiler> tag.

    It's valid in a DIFFERENT <compiler> tag (yea, confusing) according to:

    See if that helps.

    Also, right click your web project and select properties. On this screen there will be a "Target Framework" property. You can set that to 3.0.  Note that 3.0 runs on the 2.0 CLR, so in the IIS setup, it'll just be "2.0".


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