HTTP Error 503. The service is unavailable in IIS?

Question

I published my Web Api (framework 4.5) in this path:

C:\inetpub\wwwroot\MyWebAPI

In my IIS, I converted this folder to an app

When i try to access this URL http://localhost/MyWebAPI/api/client/1 the message appears:

Service Unavailable
HTTP Error 503. The service is unavailable.

Why is this?

Update

My App Pool is set to be "STOP". When I turn it on, it goes back to "STOP"

It seems that your site is not running. Please check in IIS. There is something wrong with IIS configuration. — dotnetstep, Nov 01 '16 at 13:22
A 503 error isn't enough information to diagnose anything. You'll need to provide more detail. — , Nov 01 '16 at 13:25
so the url is correct right?...the problem must be the configuration in IIs right? — Liev04, Nov 01 '16 at 13:28
We can't tell you. A 503 error isn't enough information to diagnose anything. You'll need to provide more detail. — , Nov 01 '16 at 13:29

score 9 · Accepted Answer · edited Aug 10 '21 at 22:19

I found the solution

Click on Application Pools under the tree with your machine name,
on the right side, click click on Advanced Settings,
in Process Model change the "Load User Profile" to false
Start your application and restart your IIS

The error will surely change, in my case the error changed to this one

"Config Error: This configuration section cannot be used at this path. This happens when the section is locked at a parent level. Locking is either by default (overrideModeDefault="Deny"), or set explicitly by a location tag with overrideMode="Deny" or the legacy allowOverride="false"."

I have found the solution for this other problem here Config Error: This configuration section cannot be used at this path

Jesus H Christ, my user in the app pool was stopped. Restarting it fixed the issue. Thank kind stranger. — Darth Scitus, Aug 17 '22 at 16:49

score 1 · Answer 2 · answered Feb 01 '19 at 12:20

This is a fairly old thread, but I stumbled across it with the same issue. For me, the resolution was to reset the App Pool user. I was starting the site, but the app pool would just stop. No logs, nothing. I recently had to change my windows password and the app pool user (me) was using the old password :-)

(note my website continued to work for a few days with the old password until I did an iisreset which is when the problem started)

score 0 · Answer 3 · edited Jan 31 '22 at 22:40

0

Run the following commands in PowerShell in administrator mode.

Stop-Service -Force WAS
Remove-Item -Recurse -Force C:\inetpub\temp\appPools\*
- If the above command not working, delete files manually.
Start-Service W3SVC

edited Jan 31 '22 at 22:40

Michael

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answered Dec 02 '17 at 11:23

Gehan Fernando

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score 0 · Answer 4 · answered Jan 21 '20 at 10:18

0

You might stop App pool, start it and error will be gone.

answered Jan 21 '20 at 10:18

Sheriff

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HTTP Error 503. The service is unavailable in IIS?

Update

4 Answers4

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