.NET 4.0 - CultureNotFoundException

Question

I have migrated my ASP.NET MVC 2 project to VS 2010 + .NET 4.0. Now when i start the application i get a lot of \"CultureNotFoundException\" in IntelliTrace and Output/Gebug

Answer 1

This is actually by design in System.Web (at least up until .NET Framework v4.0), not necessarily the best approach, but it works.

You can find a more detailed description here, but it basically happens because ASP.NET checks every single folder to see if it contains satellite assemblies, and throws an exception otherwise.

Given that satellite assemblies live in folders with predictable names, one would wonder why they would decide to do this rather than only check folders that match the pattern, particularly since handling exceptions is rather expensive computationally compared to a simple conditional check.

Answer 2

I was curious as to the cause to see if there was something I could personally do to eliminate this particular annoyance.

The Exception is a side effect of calling, "System.Web.UI.Util.IsCultureName(name)"

The first time it's called in my MVC3 application is in regards to a directory called "UserCache", which is in the same directory as several directories with the expected culture names "en-US", etc. .Net is trying to find Satellite directories for the application.

It's called multiple times, even relating to files that are culture files, "EditorLocalization.bg-BG.designer.cs" for example (actually all of these that are in App_GlobalResources). [ What the code does here is to take all the files in App_GlobalResources, and see if the file ends in a CultureName, again calling IsCultureName.

So there's nothing you can really do to avoid this... In production where the .cs classes won't be there, perhaps it won't happen. It certainly slows down startup quite a bit, though!

In any case, in my mind it's a total bug that Microsoft throws an exception inside, "IsCultureName().

Answer 3

Go to the Debug -> Options in Visual Studio and check "Just My Code".

Answer 4

I had a similar issue with the CultureName "UserCache". To resolve this I deleted all the folders from in here:

C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files

Answer 5

It seems as the problem was a bug in VS 2010 Beta 2.

Answer 6

For other people that have this problem, this is usually an exception that is ignored.

Go to the Debug menu -> Exceptions... and ensure that you have everything unchecked for the Exception list.