Visual Studio 2012 for Web，修复了定位框架错误

Question

I got a very weird error after my computer was a little messed up with deleting various versions of VSs and SQL Servers. It seems like i fixed the project setup and had been a "good girl" following Microsoft's advices. However here is the error!when I open my project I get this window. From what I found it that VS 2012 for web by default targets 4.5 framework, so sound like my error just should not be happening. I already tried following the second option and installing whatever it wants,unfortunately nothing has changed error message

any suggestions that wont need me to re-install the the whole thing?

Answer 1

Try the web.config as this is the area where the error will most likely reside. You can 'force' the web.config to be a specific version and I would add both c# and vb/net so they are always there. I have a web.config template I start all my projects with. Below is a cut of the part I believe you need. Just change the value of the .net

<system.codedom>
        <compilers>
            <compiler language="c#;cs;csharp" extension=".cs" warningLevel="4" type="Microsoft.CSharp.CSharpCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
                <providerOption name="CompilerVersion" value="v3.5"/>
                <providerOption name="WarnAsError" value="false"/>
            </compiler>
            <compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" warningLevel="4" type="Microsoft.VisualBasic.VBCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
                <providerOption name="CompilerVersion" value="v3.5"/>
                <providerOption name="OptionInfer" value="true"/>
                <providerOption name="WarnAsError" value="false"/>
            </compiler>
        </compilers>
    </system.codedom>