The IIS Web site app occasionally appears "Service Unavailable" or displays garbled fonts, which can be resolved using the following methods.
Cause: This situation often occurs when IIS is installed after Visual Studio or the. NET framework, and IIS does not correctly parse the ASP Web site, but it can access the HTML page normally .
1. Open the "Computer Management → services and applications →internet Information service → website", right-click on the properties of the site we decorate, open the ASP. To see if the correct is selected. NET version, in this case, the ASP. NET Web site is built in the 2.0 environment, so the ASP option is 2.0.50727, if you are developing in a. NET 4.0 environment, select 4.0.30319 and so on.
2. Open "Start → run →cmd" at the command prompt. NET environment is re-registered,
The CD is positioned to. NET installation location C:\Windows\Microsoft.NET\Framework\v4.0.30319,
Re-enroll aspnet_regiis.exe-i-enable.
An occasional "Service Unavailable" workaround appears for IIS Web site apps