Fault description:
1) IIS7.5 installed in Windows Server 2008 R2 environment
2) Installation of .Net4.5
3) Running the website, a 500 error was reported; checked the webconfig and other codes, No problem

Solution: Re-register .Net4.5, the process is as follows:
1. Start, enter the word cmd in the search box, and then the cmd.exe application appears

2. Right-click on cmd.exe and choose to run as administrator.

#3. Paste the following command into the command line window and press Enter to complete the registration.

"%WINDIR%\Microsoft.NET\Framework\v4.0.30319\aspnet_regiis.exe" -iru -enable

4. At this time, we see that in IIS, the 4.0 runtime supports successful registration.

5. Refresh IE and the website will appear normally.

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