U4-6751 - Running child application under Umbraco site - conflict if using tags in 7.2.6

Created by Tom Fulton 24 Jun 2015, 02:49:05 Updated by Shannon Deminick 26 Jun 2017, 07:13:12

''Disclaimer: This might not be an "issue", but thought I'd bring to your attention just in case as it requires a change in behavior.''

Typically when we want to run another application underneath an Umbraco site, we'll:

  • Create an application under the Umbraco site in IIS
  • Add <location> tags to Umbraco's web.config to prevent Umbraco's settings from trickling down (otherwise, sub-app gets YSOD trying to load Umbraco stuff) (refs: [http://codeblog.shawson.co.uk/stop-the-web-config-being-inherited-by-child-applications-in-sub-folders/ 1] [https://our.umbraco.org/forum/getting-started/installing-umbraco/6825-web-application-inside-umbraco-site-in-iis 2] [https://our.umbraco.org/forum/getting-started/installing-umbraco/16868-Non-Umbraco-Virtual-Directory?p=0 3])

This process doesn't seem to work starting in Umbraco ~7.2.6, it causes a server error when trying to access the Umbraco backoffice (attached):

HTTP Error 500.22 - Internal Server Error An ASP.NET setting has been detected that does not apply in Integrated managed pipeline mode.

The cause seems to be the new [https://github.com/umbraco/Umbraco-CMS/commit/0df0b78b908e505e47452eb5cd31528004350021 ] element that now ships in Umbraco's web.config (I think it was for: U4-5453). If you remove this, all seems to work fine again. I'm not sure exactly why this is happening, just appears to be some sort of conflict with the two tags/paths.

This might not be an Umbraco issue per se, maybe it just requires a change in the way we (+ others?) usually configure sub-applications. I think there are other ways to make it work, but thought I'd flag it here just in case :)

'''Forum posts of people having this issue:''' https://our.umbraco.org/forum/getting-started/installing-umbraco/66756-problem-running-separate-app-in-umbraco-site#comment-222428

'''Steps to reproduce:'''

  • Install a fresh copy of 7.2.6 as an IIS site
  • Create a directory anywhere on your filesystem called myapp, add an index.html file with contents: Hello World
  • In IIS, right-click your site and click Add Application, name it "myapp" and point it to the "myapp" folder created above
  • Update Umbraco's web.config by adding <location> tags, to allow your sub application to work and not inherit Umbraco's web.config <system.web>...</system.web> <system.webServer>...</system.webServer>
  • Attempt to visit your Umbraco backoffice, you'll get the attached server error
  • Remove this portion from Umbraco's web.config, and all should work again, including access to your sub-app at /myapp/index.html <system.webServer> </system.webServer>

1 Attachments


Andrew Ellis-Chadwick 20 Jul 2015, 14:22:03

Got this issue after an upgrade from 7.1.4 to 7.2.2 As soon as I remove the site works fine.

Tom Jenks 05 Aug 2015, 10:52:54

We also ran into this today, it turns out you can just add So the Umbraco location becomes <system.webServer> </system.webServer>

Instead of removing the whole section, I think it happens when wrapping the whole system.webserver section, so umbraco doesn't know to not validate the integrated config. Adding it back in tells Umbraco to behave ;)

Shannon Deminick 26 Jun 2017, 07:13:12

Closing issue due to inactivity - see blog post for details https://umbraco.com/blog/issue-tracker-cleanup/

Priority: Normal

Type: Bug

State: Closed


Difficulty: Normal

Category: Installation

Backwards Compatible: True

Fix Submitted:

Affected versions: 7.2.6

Due in version:


Story Points: