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Unable to run blazor app - get 502.5 error (Blazor 0.8.0) #7302

Closed danroth27 closed 5 years ago

danroth27 commented 5 years ago

From @henrikmbach on Wednesday, 06 February 2019 14:46:21

VS 2019 Preview 2.2 Blazor 0.8.0

I get this error in my browser: "HTTP Error 502.5 - Process Failure"

"dotnet --info" on command line gives me: .NET Core SDK (reflecting any global.json): Version: 3.0.100-preview-010184

There is no global.json that I can delete from my project (it fixed the problem I had on an earlier version of Blazor).

In the "New ASP.NET Core Web Application" dialog I have selected "Blazor" from the list of templates (not "Razor Components" as described in the getting started thing on the Blazor homepage). Ctrl-F5 gives me the above error in my browser.

NB! If I select "Razor Components" instead of "Blazor" described above, Ctrl-F5 works fine. So it appears that the option "Blazor" is broken.

Copied from original issue: aspnet/Blazor#1781

danroth27 commented 5 years ago

@henrikmbach Thanks for reporting this issue! I'm sorry you're having trouble getting going with Blazor 0.8.0.

Could you please try switching the Blazor app to run as a standalone project instead of running behind IIS Express and then see what errors show up in the console logs? To do this open a command prompt in the directory of the Blazor app and type dotnet run. Report any errors you see here.

henrikmbach commented 5 years ago

It works fine without IIS express. Then I tried to use the Blazor 0.8.0 the normal way and it also worked fine, so this problem was temporary. This issue can be closed.

danroth27 commented 5 years ago

Got it. This may have been due to a known issue with the Blazor template when it is the first .NET Core app run. We should have this addressed in a future release.

joshcomley commented 5 years ago

I am having the exact same issue with a fresh install of Blazor and the exact same configuration.

How do I configure it to run standalone? If I try to use dotnet run from the command line all I get is:

Unable to generate deps.json, it may have been already generated.  You can specify the "-d" option before the tool name for diagnostic output (for example, "dotnet -d <toolname>": C:\Program Files\dotnet\sdk\3.0.100-preview-010184\Sdks\Microsoft.NET.Sdk\targets\GenerateDeps\GenerateDeps.proj

How can I proceed?

danroth27 commented 5 years ago

@joshcomley This is a known issue with the current preview of .NET Core 3.0. You may see this error when running a standalone Blazor app and you haven't yet restored packages for any .NET Core apps. To workaround this issue create any .NET Core app (ex dotnet new console) and then rerun the Blazor app.

joshcomley commented 5 years ago

@danroth27 thank you, following your instructions got things working for me