Type or namespace name "" Not Found (is missing a using directive or assembly reference?)

Original: http://www.cnblogs.com/zhangzhifeng/p/3607519.html

Symptom: The project was compiled with a hint that the type or namespace name "" was not found (is missing a using directive or assembly reference?)

Workaround:

If the type is not found, check whether the namespace that contains the type is referenced and use the using directive.
If the namespace is not found, then check to see if the assembly is referenced.

If you confirm that the assembly is referenced, check that the assembly version and project are consistent, for example, your project is. NET 4.0, and your assembly is compiled under. NET 3.5, (right-click the project, properties, view build, Target framework)

Or your reference project is not the same as the. NET Framework version of the referenced project, for example, one is. NET 4.0 and the other is. NET 4.0 Client profile.

Type or namespace name "" Not Found (is missing a using directive or assembly reference?)