Bug The MonoDevelop version bundled with 5.5.0b2 crashes on startup

The version of MonoDevelop included with Unity 5.5.0b2 just won't start at all, and gives no error messages when you try to open the GUI either directly or through Unity.

When run from the terminal, I get the following error message:

~$ /opt/Unity/MonoDevelop/bin/monodevelop

Unhandled Exception:
System.TypeLoadException: Failure has occurred while loading a type.
at MonoDevelop.Startup.MonoDevelopMain.Main (System.String[] args) <0x40048e80 + 0x0000f> in <filename unknown>:0
[ERROR] FATAL UNHANDLED EXCEPTION: System.TypeLoadException: Failure has occurred while loading a type.
at MonoDevelop.Startup.MonoDevelopMain.Main (System.String[] args) <0x40048e80 + 0x0000f> in <filename unknown>:0 ​

I had the same problem in the previous version I had (I think it was 5.1?). Because of this, I have just been using GEdit (it has code coloring, but no code hinting). Last time, I was eventually able to get MonoDevelop working by installing it directly from the Ubuntu repositories, and ignoring the version bundled with Unity. I have no idea which version of MonoDevelop is included with 5.5.0b2 since I can't even run it in the terminal with a --help flag.

 

The monodevelop executable supplied with 5.5.0b2 works on my Arch Linux system. Did you try reinstalling Unity?

 

I thought I mentioned it in the post, but I guess I forgot, I am running Ubuntu 16.04 - 64 bit Desktop version, Linux kernel 4.4.0-36-generic.

Yep, fresh install (that same day) of both the OS and Unity. And as I said, I had the same problem with MonoDevelop in the previous version I had, never have been able to get it work unless I install it separately.

I would have submit this to the bug tracker, but I have no idea if (1) MonoDevelop bugs are handled by the Unity team and (2) if Linux bugs should be submitted to the Unity bugtracker, or elsewhere. I figured I'd start in this section of the forums.

 

I had the same issue, running it from the terminal presented:

Code (sh):

1. Unhandled Exception:
2. System.TypeLoadException: Failure has occurred while loading a type.
3.   at MonoDevelop.Startup.MonoDevelopMain.Main (System.String[] args) <0x40066e80 + 0x0000f> in <filename unknown>:0
4. [ERROR] FATAL UNHANDLED EXCEPTION: System.TypeLoadException: Failure has occurred while loading a type.
5.   at MonoDevelop.Startup.MonoDevelopMain.Main (System.String[] args) <0x40066e80 + 0x0000f> in <filename unknown>:0

Doing a quick google a stack overflow response stated that they were able to overcome the issue by installing gtk-sharp2.

Code (sh):

1. apt-get install gtk-sharp2

I can verify that solved my problem when using (using ubuntu 16.04) and unity 5.5b5. Hopefully it will help you also.

This should allow monodevelop to start. (but might complain about not having the gnome-sharp2 platform assemblies...

Code (sh):

1. apt-get install gtk-gnome-sharp2

solve this for me.