StackOverflowException: Aspnet_wp.exe (PID: [number]) stopped unexpectedly.

Yesterday I was trying to guess what the hell is going on with my application. You see, I was moving controls from one panel to the other in case the browser was FireFox and I forgot all about it. In Internet Explorer it would work, in FireFox ASP.Net would crash, with a Server not available error and not any relevant message as to why. In the Application Event Log I would get stuff like:
aspnet_wp.exe (PID: 872) stopped unexpectedly.
and
EventType clr20r3, P1 aspnet_wp.exe, P2 2.0.50727.832, P3 461ef1db, P4 system, P5 2.0.0.0, P6 461ef191, P7 143a, P8 1f, P9 system.stackoverflowexception, P10 NIL.

and no explanations. Google would give me a lot of links that pertained to WebServices and Asynchronous operations and multi threading, but my application is a simple app. What was going on?

It turns out I was doing this:
pnlNoAjax.Controls.Add(UpdatePanel1.ContentTemplateContainer.Controls[0]);
Nothing wrong with it, except the control that I was adding was also pnlNoAjax and so it went round and round chasing its own tail until a stack overflow exception was generated.

So, bottom line: try to see if you don't have a control adding itself to its control collection when you meet this weird error. Or, of course, the problem might be in a WebService or threading operation :)

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Disabling ASP.Net Ajax on a page with UpdatePanels

You have one beautiful page with Ajax.Net, UpdatePanels and the sorts. Then you go test it with FireFox and it doesn't work. Or you have some other reason for not wanting Ajax in certain situations, like for example people with no Javascript. So what do you do? How can you tell the page NOT to do Ajax postbacks?

The solution is to set ScriptManager's EnablePartialRendering to false. I used to do it with a Panel that was outside the UpdatePanel and in the page Init cycle I would move all controls from the update panel to this normal panel. And it worked, too.

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INSERT or UPDATE or DELETE failed because the following SET options have incorrect settings: 'ARITHABORT' or something else

Quick fix: look for indexed views or indexes on tables with computed columns and delete the index or change it to not reference the view or the computed column.

I got this error while trying to optimize an SQL server. I did the trace, I used the Database Engine Tuning Advisor, it gave me an sql file of magical Create Statistics and Create Index lines. But after I applied it, happy that I will get a 38% increase in my SQL speed, I got this weird error:
UPDATE failed because the following SET options have incorrect settings: 'ARITHABORT'

I wasn't aware that a cluster could break your database! So I found this little Microsoft article: PRB: Error "INSERT Failed" When You Update Table Referenced in an Indexed View.

Yet it only speaks about Indexed Views and it somehow shifts the blame to some missing ArithAbort setting. Not so. In my case it was about one of the indexes referencing a computed column in the INCLUDE statement.

In my particular case, changing the offending index to not reference the computed column was the solution. Of course, indexing computed columns and views is totally possibly, but it depends on how you create those indexes. In my case, SET ARITHABORT ON was set before creating the index. The solution in the Microsoft Support article might be better, even if less attractive to lazy people as myself.

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Thread was being aborted exception - possible solutions and unsolved problems

Update February 2016: This post discusses a problem in .Net 2.0 that is more than 8 years old. Perhaps you should look elsewhere. That being said, there are several situations here:

1. The default execution timeout is 90 in ASP.Net, increase it to whatever you like (in seconds) with <system.web>
      <httpRuntime executionTimeout="VALUE" />
   </system.web>
   Also read this: What exactly is Appdomain recycling, since it is likely this applies in a lot more situations where the server decides the app needs to be recycled.
2. You use a Response.Redirect, Server.Transfer or Response.End directly, which is the method that ultimately throws this exception. Response.Redirect has an optional bool parameter that, when set to false, does not execute Response.End. Response.End itself is obsolete, recommended is the HttpApplication.CompleteRequest method. Read the remarks for Response.End, it is a method exclusively left there as for compatibility with ASP and it is pretty damn awful. See here how to replace Response.End.
3. The original problem that made me write this post, which was a long running method inside a web service in .Net 2.0, to which I have not found the solution back then. The solution is probably related to AppDomain/Application Pool recycling from the first point and at that time I did not look hard enough at all application pool settings.
4. Some issues encountered by other readers that were caused by the ASP.Net application writing in its bin folder, causing the automatic recompiling of the app.

Read more about the ThreadAbortException, which is raised when aborting a thread, which in itself is a pretty bad idea. Ultimately, I would say that getting this exception nowadays is a sure sign of bad design.

Now for the original post:

Update: the problem I was facing is still there and with no solution. I must be doing something wrong, but I can't figure out what. It involves a web service in NET 2.0, added with Web Reference in another app. The service has a method that takes a lot of time. If I do it synchronously it works, depending on the Timeout property of the web service proxy and the executionTimeout setting in the web.config. If I do it asynchronously, though, it doesn't work! If it takes too long it just kills the thread. The Timeout property of the web service doesn't even count in async calls. My solution was to call the method synchronously and be done with it. If anyone has an answer for this, please let me know!

(Oh, but if you mean to tell me that an asynchronous operation in a web service should not take long and that it is bad design and so on and so on, don't let me know!)

The single most related article to my problem that I found on the net is this: timeout problem with webservice and suggests a client problem, but no solution other than asynchronously calling the synchronous call to the web service, and no explanation to the underlying problem.

As for the regular solution for Thread being aborted, it actually it's not my solution, it was given in a forum by a guy with the nickname dstefanov, but I stole it with impunity :)

Here it is:
ThreadAbortException happens when the thread serving the request doesn't finish for a long time. The ASP.NET hosting process aborts this thread after certain time. You can adjust that time with:

<system.web>
<httpRuntime executionTimeout="600" />
</system.web>

By default the executionTimeout="90" seconds.

This applies to ASP.Net web apps, including web services, so also to console or windows forms applications that use web services. My own personal favourite is 86400, the number of seconds in a day.

Thanks dstefanov!

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Jem - They

I saw this chick sing "They" on Mtv. She was stripping in space in that video, a thing that I found a bit distasteful, even if it did link to a Jane Fonda scene in a film called Barbarella, Queen of the Galaxy. But that's the MTV world: strip if you want to get noticed. True enough, I haven't seen any other of her videos on any music television since, but then I stopped watching them.

Jem (real name Jemma Griffiths) is a Welsh singer and this is (I guess) the original video of "They". She is young, beautiful, but also has a nice voice and sound. Check her out at her official web site or the MySpace site.

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ASP.Net Ajax, UpdatePanel, PageRequestManager, Dan Wahlin

I had to rewrite the entire post. It started from a nice article by a guy called Dan Wahlin and it ended with three (at least? :) ) separate links to his articles and his blog entered in my Technorati favourites.

Here are links to what appears to be a series about Asp.Net Ajax, really informative and concise:

Update Panel properties explained: Implement UpdatePanel Properties

Implement visual cues during updates:Inform Users With Customized Visual Feedback

Minimize the load on the server on many subsequent clicks or refresh requests:Coping With Click-Happy Users

Here is a complete list of the links in the same series:
ASP.NET AJAX Articles

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Steroids for the brain: ampakine

I've found this while randomly browsing the net, a substance that is supposed to be increasing memory and brain plasticity called ampakine. An article called it steroids for the brain and I borrowed that in the title, since I found it is appropriate enough.

Like all mind enhancing drugs it was discovered by accident, while working on a cure for Alzheimer. Why would anyone try to enhance one's brain on purpose, anyway? :-|

I am not much of a biochemist (even if I recently made some acquaintances that are :) and I could ask them to enlighten me) so I will just post a list of links that I found on the subject. It seems that there are no publicly available pills yet, as the drug is still in trials, but who knows... maybe we can become smarter rather than dumber for a change.

Here are the links:

ampakines
A profile of the behavioral changes produced by
facilitation of AMPA-type glutamate receptors
ampakine
Ampakines
'Memory pill' for the forgetful

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