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I am trying to open a simple executable using Mono, as Wine told me to install Mono for .net applications, and this is the error I get

    mono yt.exe

** Message: Unknown heap type: #GUlD

** Message: Unknown heap type: #Blop

** (yt.exe:2508): WARNING **: The following assembly referenced from /home/austin/Downloads/yt.exe could not be loaded:

     Assembly:   System.Windows.Forms    (assemblyref_index=0)


     Public Key: b77a5c561934e089

The assembly was not found in the Global Assembly Cache, a path listed in the MONO_PATH environment variable, or in the location of the executing assembly (/home/austin/Downloads/).

** (yt.exe:2508): WARNING **: Could not load file or assembly 'System.Windows.Forms, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies.

** (yt.exe:2508): WARNING **: Missing method EnableVisualStyles in assembly /home/austin/Downloads/yt.exe, type System.Windows.Forms.Application

Unhandled Exception: System.IO.FileNotFoundException: Could not load file or assembly 'System.Windows.Forms, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies.

File name: 'System.Windows.Forms, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089'

Thanks for any help, i've looked everywhere and can't figure out what's wrong.

share|improve this question

The Mono version present in the repositories (2.6.7) is able to run only .NET 3.5 applications, and yours is .NET 4. To run your application you probably need Mono 2.8 or, even better, 2.10.2. I don't know which are the plans to put those frameworks in the official repositories (I do hope for the next ubuntu but I don't think so). Anyway, googling for mono 2.10.2, you'd be able to find some guides to install a parallel mono environment able to run .NET 4 applications :)

I hope to be helpful, Mat.

share|improve this answer
Thanks, I'm trying a guide right now, hopefully works, i'll let you know. Thanks again. – Austin Jun 27 '11 at 10:23
mono 2.10 is already in ubuntu 11.10 – trampster Jun 27 '11 at 10:32
that sounds great! thanks a lot trampster, that will make my boss at work very happy (and me too, forced to work with opensuse right now :D) – Mattia Vitturi Jun 27 '11 at 10:32
@trampster With 11.04 the lastest version of ubuntu, I don't really see how that helps me :( And I'm using… that guide, will that work you think? – Austin Jun 27 '11 at 10:35
@Austin I'd use that guide too. Actually what scares me a bit is the fact your application is using System.Windows.Forms, and I don't know how much of that has been implemented in mono. I'd say that for .NET 4 mono console applications the support is very good but ... eh, the 'visual part', is a little problem. – Mattia Vitturi Jun 27 '11 at 10:38

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