[Resolved] Could not load file or assembly 'XXXXX' or one of its dependencies. An attempt was made to load a program with an incorrect format.

Sunday, October 11, 2009

I have recently switched my development environment from 32-bit to 64-bit by installing Windows Server 2008 64-bit and modify it to be used as workstation as described here http://www.win2008workstation.com/ and I'm really amazed with it’s performance.

I have faced the problem mentioned in the post title when I'm trying to run a web application included in one of our development solutions.

I have checked the project which has the DBHelper as it’s output and I’ve discovered that the project configured to target x86 platform and as I'm working with 64-bit it will have such ‘incorrect format’ error.

How to fix it:

Simply follow the steps below :

open project properties window.
select Build tab
Change it to ‘Any CPU’
Save your changes.
Compile your project and run :)

9 Comments

Hi,

I have a web site project (VS 2008) that has the build configuration set to Any CPU but still getting the same error for an assembly. Any other steps to solve this?

Thanks,
Gopalakrishnan

Gopalakrishnan - Sunday, October 18, 2009 10:45:23 AM

Hello Gopalakrishnan,

please make sure you have did so for all dependencies your website uses.

You can also enable 32-bit mode on IIS and adjust your website and its dependencies to target 86x platform.

let me know if this doesn't work for you.

HosamKamel - Sunday, October 18, 2009 11:48:39 AM

Thank you so much your few lines, fix one day of failed research
I'm using Windows 7 64 bit , however it works fine when i switch to x86 !!!

Feras - Thursday, December 31, 2009 5:59:08 AM

Thanks a bunch. Spent about an hour before finding this post. Glad I got luckly and didn't waste a day or more.

Changing the dependent project to 'Any CPU' worked for me.

Mateo - Monday, March 1, 2010 9:34:31 PM

I figured out it happened for my WCF project in case I added string

in my web.config inside service configuration section. As I remove it, everything works fine.

Yuri - Friday, April 9, 2010 5:04:19 PM

Thanks man. Saved me some time with this post :)
D.

Dean - Tuesday, June 15, 2010 9:57:59 PM

Thanks for the hint! Saved me hours of searching, had already invested a couple of hours trying everything else!

DannyC - Monday, September 13, 2010 9:27:46 PM

Thanks Man

manoj22184 - Friday, September 30, 2011 3:07:42 PM

Great. Thanks for the help!

bubba - Thursday, November 3, 2011 2:29:45 PM

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