We Keep Coding

CS0246: The type or namespace name 'MySql' could not be found

how i can fix this problem??
help me
Compiler Error Message: CS0246: The type or namespace name 'MySql' could not be found (are you missing a using directive or an assembly reference?)
Line 1: using MySql.Data.MySqlClient;

Apologies if this is not the case but working on the assumption that you're developing in a version of Visual Studio, check the project references.
If MySql.Data exists in the references but has the warning (yellow triangle) indicator next to it then you may need to re-reference the .dll from its location in your filesystem.
Alternatively, you can grab this from the Nuget package manager if it is not available locally.
Despite the full namespace qualification, the library must be correctly referenced for the object namespace to be recognised in the IDE.
Let us know what IDE you're using if not VS.

System.Net.Http Unavailable for .Net 4.5 Application. Reference Has Been Added

I have a .Net 4.5 application. It has a reference added to System.Net.Http, but when I add the line
using System.Net.Http;
I get the error:
Error CS0234 The type or namespace name 'Http' does not exist in the namespace 'System.Net' (are you missing an assembly reference?)
The assembly reference is there for System.Net.Http v4.0.30319.
I've tried adding the Nuget package for System.Net.Http v4.3.3 and still the same thing.
Http shows in my list as unavailable.
Little help?
Thanks.

Several system libraries missing in a VS Express install

I am having a problem I am trying to troubleshoot. I developed a website in VS 2013, and am trying to set the website up for continuous integration on a server using teamcity.
I have already tested teamcity on my computer, and have it compiling perfectly using a VS2013 install.
On the server, I have everything working...except for the compilation. In order to compile the website, I installed VS Express on the server. The problem is, a new error is appearing on the server:
System.Net.Http.Formatting and
System.Web.Http
...are both missing.
Are they missing because of some error? Because I am using VSExpress instead of VS2013?
The actual error is:
Security\ApiAuthentication.cs(7, 23): error CS0234: The type or namespace name 'Formatting' does not exist in the namespace 'System.Net.Http' (are you missing an assembly reference?)
Security\ApiAuthentication.cs(12, 18): error CS0234: The type or namespace name 'Http' does not exist in the namespace 'System.Web' (are you missing an assembly reference?)
Security\ApiAuthentication.cs(21, 49): error CS0234: The type or namespace name 'Http' does not exist in the namespace 'System.Web' (are you missing an assembly reference?)
Security\ApiAuthentication.cs(32, 48): error CS0246: The type or namespace name 'HttpActionContext' could not be found (are you missing a using directive or an assembly reference?)

I've got VS Community 2013 on my local, in the base install the System.Net.Http namespace exists but System.Net.Http.Formatting does not. This is the same with System.Web vs System.Web.Http.
On installing the Microsoft.AspNet.WebApi.Core NuGet package both appeared as expected and could be referenced.
Have you tried adding a NuGet Restore step to your TeamCity build before compiling? It's strange mind that these are the only errors you are seeing if there's been no NuGet restore in place. Maybe a build order issue / red herring?

The type or namespace name could not be found. SeleniumBasicAuthWrapper

I have created unit test project in VS12 and installed package 'SeleniumBasicAuthWrapper' from NuGet.
When I add
using SeleniumBasicAuth;
and try to build project I get following error message:
Error 2 The type or namespace name 'SeleniumBasicAuth' could not be
found (are you missing a using directive or an assembly reference?)

TFS build - Getting error

I have configured tfs build definition for our project. And also i have added Nuget package to the solution.
When i tried to build the defination, i'm getting following error.
App_Start\BundleConfig.cs (7): The type or namespace name 'Optimization' does not exist in the namespace 'System.Web' (are you missing an assembly reference?)
Global.asax.cs (10): The type or namespace name 'Optimization' does not exist in the namespace 'System.Web' (are you missing an assembly reference?)
App_Start\BundleConfig.cs (20): The type or namespace name 'BundleCollection' could not be found (are you missing a using directive or an assembly reference?)
I don't know why i'm getting this error.
Could anyone please help me with this????

Check your Build definition -> Source Settings tab. You should add path to packages folder where referenced packages are stored.