I wanted to run my software on a VPS, however, when I try to run it with mono, it says

The assembly mscorlib.dll was not found or could not be loaded.It should have been installed in the '/usr/local/lib/mono/4.5/mscorlib.dll' directory.

I've already tried to install mono-complete

sudo apt-get install mono-complete

However, it says mono-complete is already the newest version.

Is there anything I can do to fix it?

Sincerely, Mike

( I run on my VPS on ubuntu 13.10 64 bit, and my mono version is 4.0.0)

I came across the problem last day.You need to install mono-2.0 to execute certain programs.

To install mono 2.0 ,open terminal and type

sudo apt-get install libmono2.0-cil
  • Hi, Thanks for your reply, it didn't work though, it's already the newest version – Mike Feb 20 '14 at 15:40
  • @mike version 2.0 is different than 4.0 .They can be both installed at same time.If the command doesn't work, try software center. – Registered User Feb 21 '14 at 9:23
  • I probably explained the it the wrong way, when I executed the command, it says it couldn't install because it was already the latest version – Mike Feb 21 '14 at 11:30
  • try sudo apt-get install libmono-system2.0-cil – Registered User Feb 21 '14 at 11:40
  • Also already the newest version – Mike Feb 21 '14 at 15:40

I had the same problem with my brother's computer. It seems to be an installation problem. MonoDevelop thinks mono's libraries are installed in /usr/local/lib/... I couldn't fix that problem, so I copied /usr/lib/mono to /usr/local/lib

sudo cp -r /usr/lib/mono /usr/local/lib/

That works for now, but that isn't the solution. Anyone knows how to tell MonoDevelop where to look for the libraries? without having to build/install it manually.

  • You could use a symlink instead of copying. – Volker Siegel Oct 19 '14 at 0:01
  • Yes, it's better :) I did that after. And also, I set MONO_PATH correctly. – Nemo Oct 19 '14 at 1:44

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