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Question: How do you solve for this error in IIS hosting Asp.Net 5: "HTTP Error 500.30 - ASP.NET Core app failed to start"
Command solution to this issue:
1. The app failed to start
2. The app restarted but then stopped
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Answer: To be able to troubleshoot this issue is mainly with the appsettings.json, the error is caused by the unwanted charecter in the appsettings.json. To find out exactly what the cause of the HTTP Error 500.30 is, start an application called EventViewer and navigate to System Events. You will be able to see an Event Log of IIS and the main cause of an Error.
Here are few things to avoid when working with appsettings.json file in Production Environment hosting Asp.Net Core or .Net 5 in IIS.
1. Avoid Copying and Pasting Values into appsettings.json (this will result into pasting unwanted characters and introduce all lots of problems)
2. Stop both the IIS and the App then work on the appsettings.json
3. If the problem persists, open up Powershell as Admin and type iisreset (this will stop and restart the IIS)
Question
How do you solve for this error in IIS hosting Asp.Net 5
"HTTP Error 500.30 - ASP.NET Core app failed to start"
Command solution to this issue
1. The app failed to start
2. The app restarted but then stopped
Answer
To be able to troubleshoot this issue is mainly with the appsettings.json, the error is caused by the unwanted character in the appsettings.json. To find out exactly what the cause of the HTTP Error 500.30 is, start an application called EventViewer and navigate to System Events. You will be able to see an Event Log of IIS and the main cause of an Error.
Here are a few things to avoid when working with the appsettings.json file in the Production Environment hosting Asp.Net Core or .Net 5 in IIS.
1. Avoid Copying and Pasting Values into appsettings.json (this will result in pasting unwanted characters and introduce all lots of problems)
2. Stop both the IIS and the App then work on the appsettings.json
3. If the problem persists, open up Powershell as Admin and type iisreset (this will stop and restart the IIS)
If you are wondering how to see the Event Logs on Windows.
1. Go to the Search bar (the one next to the Windows menu) then search for EventViewer
2. Select the app and start it. 3. Navigate to SystemLogs, then Application Logs, you will be able to see Asp or IIS logs. This is the best way to see the errors.
4. If you can't see the error in the logs due to a lot of Warning logs, on the right-hand side there is a Filter Log link, click on it to filter and see only Errors.
Question
How do you solve for this error in IIS hosting Asp.Net 5
"HTTP Error 500.30 - ASP.NET Core app failed to start"
Command solution to this issue
1. The app failed to start
2. The app restarted but then stopped
Answer
To be able to troubleshoot this issue is mainly with the appsettings.json, the error is caused by the unwanted charecter in the appsettings.json. To find out exactly what the cause of the HTTP Error 500.30 is, start an application called EventViewer and navigate to System Events. You will be able to see an Event Log of IIS and the main cause of an Error.
Here are few things to avoid when working with appsettings.json file in Production Environment hosting Asp.Net Core or .Net 5 in IIS.
1. Avoid Copying and Pasting Values into appsettings.json (this will result into pasting unwanted characters and introduce all lots of problems)
2. Stop both the IIS and the App then work on the appsettings.json
3. If the problem persists, open up Powershell as Admin and type iisreset (this will stop and restart the IIS)
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Andrew said:
Another thing I found was that IIS was caching appsettings.json, if you want to edit appsettings.json first stop the IIS Web Server, make sure the WebServer is stopped then modify the appsettings.json. After the modification is done then restart the IIS.