Please follow the steps given below .
- Open IIS on your system
- Go to Application pools and check the ASP.NET V4.0
- Run command prompt as Administrator
- Run the command C:\Windows\Microsoft.NET\Framework64\v4.0.30319\aspnet_regiis.exe –u
- It will start uninstalling ASP.NET v4.0.30319
- Run the command C:\Windows\Microsoft.NET\Framework64\v4.0.30319\aspnet_regiis.exe –ir
- It will start installing ASP.NET without changing the existing web applications
- Restart your IIS
Please go through the below given screenshot for further reference: