ApplicationPoolIdentity >> IIS 7 and Application Pool Shutting down behavior with Error 503 followed by HTTP Error 401.3

Recently while deploying one of our website to IIS of a new production server (Windows 2012 Server), I was facing a weird issue. Whenever a user tries to launch the website, the application pool was getting crashed with Error - 503. 

The application pool was running under "ApplicationPoolIdentity" account.

After investigating the event logs, I found the root cause of the issue as below: 

Windows cannot copy file \\?\C:\Users\Default\AppData\Local\Microsoft\VSCommon\14.0\SQM\sqmdata00.sqm to location \\?\C:\Users\XXXXX.IIS APPPOOL.008\AppData\Local\Microsoft\VSCommon\14.0\SQM\sqmdata00.sqm. This error may be caused by network problems or insufficient security rights.
 DETAIL - Access is denied.

The issue was related to security which is quite apparent from the error message, but it was something new for me, especially after successfully deploying more than 100 ASP.NET websites.

After a lot of research, I found following had to be done to resolve this issue -

1. Open the properties of "Default" user (i.e., "C:\Users\Default". Location may defer based on the installation).

2. Under Security, click "Advanced" followed to that click "Change Permissions". This should open "Advanced Security Settings for Default" dialog box.

3. Tick "Replace all child object permissions with inheritable permissions for this object" check box.

4. Click Apply and OK.

Now restart the application pool, and try accessing the website. This should fix the issue.

However, for me, it didn't end there. This resolved the 503 error, I was able to see the website getting loaded in the browser, and application pool was not shutting down which was perfect solution. But now, it was not loading any unmanaged resources (i.e., css, js, images, etc). 

Further more investigations suggested that all these resources were failing to load due to "401.3 Unauthorized" error.

After another round of research and googling, I found the root cause which was even more strange.

1. Open "Authentication" settings of the website under IIS.

2. Select "Anonymous Authentication", and click "Edit" button.

3. Check which option is selected under "Anonymous user identity". If it is "Specific user", then congratulations, your problem will be resolved in a minute.

4. Change the option to "Application pool identity", and click "OK"

Restart Application Pool, and relaunch the website.

This time, the website should load properly and all expected resources.

Hope this helps

Error 403, 403.14, 404 - After deploying ASP.NET MVC website on IIS 7, IIS 7.5

After deploying your ASP.NET MVC website on IIS 7 or IIS 7.5, you might face following errors while browsing your website:

• 403.14 - Forbidden (The Web server is configured to not list the contents of this directory.)
• 404 - Not Found (The resource you are looking for has been removed, had its name changed, or is temporarily unavailable)

Following are the possible causes/ fixes for this -

• Make sure the Application pool targets correct version of .NET framework (i.e .NET Framework v4.0.30319 for .NET 4 and 4.5)
• Make sure the Pipeline mode of IIS Application pool is "Integrated"
• Check UrlRoutingModule-4.0 is added in the modules of that website.
• (To do that, open list of added modules by clicking "Modules" against your website, and see if the module "UrlRoutingModule-4.0" is added or not). If not, then add a module by clicking "Add Managed Module" button, where select System.Web.Routing.UrlRoutingModule as a Module type, and give "UrlRoutingModule-4.0" as its name)
• Make sure you have following element added in system.webServer section of website's web.config

<system.webServer>

<modules runAllManagedModulesForAllRequests="true"></modules> 

</system.webServer>

In most cases of 403.14, or 404 error, above are the possible causes and fixes. 

FIX: An MVC website configured for Windows Authentication is trying to redirect to Login page while accessing from IIS

I came across a very strange issue recently. My MVC application was configured to use Windows Authentication, and it was deployed on IIS.
While the website was working very properly when accessed from Development environment, means, it was taking the routes into considerations and was properly redirecting the user to specific routes. However, while accessing the website from IIS, it was straight-away redirecting user to a login page. (which obviously was throwing the error, as the windows application is not suppose to have login page).
I checked all configurations on IIS, and also could see only 'Windows Authentication" enabled, which was quite correct.
Though I haven't found any particular reason why it would be happening, however, I learned how to fix this :)
Add following keys in "<appSettings>" section of application's web.config file.

<add key="autoFormsAuthentication" value="false" />
<add key="enableSimpleMembership" value="false"/>

and restart the site on IIS. That should do the magic!
If the issue is too strange, the solution is more than strange...

Hope this saves someone's time and effort :)

CodeProject

Investigations:Could not load file or assembly or one of its dependencies.An attempt was made to load a program with an incorrect format.

ERROR: Could not load file or assembly or one of its dependencies.An attempt was made to load a program with an incorrect format. 

Developers generally face this issue in production server, or running a web application under IIS.

The site works fine in the integrated development environment, but fails and giving this error while running it in IIS.

The most likely reason of this issue is the incompatibility of target platforms. 

Say, your  application is targettng to only x32, but the dependent assembly targets to "Any CPU", or vice versa.

In order to fix this issue, you need to change settings of relevant Application Pool in IIS, to allow 32-bit applications.

This should resolve the issue.

Development and Deployment - Troubleshooting, Investigations (Series of articles)

At times, we, developers or deployment people do come across some technical problems that eat up our hours (and days sometimes).. and when we find the resolution, or real cause of the issue, it makes us feel that such issues were not worth of the time and efforts we spent.

Here, I am making a collection of such issues/ troubleshooting notes that may help us to take extra care in order to avoid that issues raising while we develop or deploy.

There are each new post for each different issue/ troubleshooting note, and this post is an index that will keep growing as I add new post in this category.

Keep checking this place regularly.

INDEX:

ASP.NET

1. ExecuteNonQuery() always returns -1

2. SelectedIndexChanged not firing up

ASP.NET MVC

1. Values do not retain in model while posting it from view to controller action in MVC