Getting Could not resolve mscorlib for target framework '.NETFramework,Version=v4.8'. This can happen if the target framework is not installed or if the framework moniker is incorrectly formatted. When trying to "view designer" in Visual Studio for class.

Question

Hello, need help with this error |Could not resolve mscorlib for target framework '.NETFramework,Version=v4.8'.
This can happen if the target framework is not installed or if the framework
moniker is incorrectly formatted.|Could not resolve mscorlib for target framework '.NETFramework,Version=v4.8'.
This can happen if the target framework is not installed or if the framework
moniker is incorrectly formatted.| | -------- | -------- | |Don't know what i'm supposed to do to resolve this and be able to view designer. Thanks!|

Answer 1

I had this same issue in my VB.NET WinForms project in Visual Studio 2026 recently.

It worked again after I explicitly re-referenced the mscorlib assembly in the assembly references in my project.

Answer 2

Hi @Brandon Dickinson , Welcome to Microsoft Q&A,

Assuming you are using Visual Studio,

If this is your first time using Visual Studio, it is recommended that you check whether .Net Framework 4.8 in the installer is installed correctly.

Secondly, you can try to see if the path length in your working path is too long and try to use a shorter path.

Finally you can also try clean project, then retargeted from 4.8 to 4.7.2 and back.

Here is a similar question.

Best Regards,

Jiale

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