MonoDevelop not launching 4.3.4

I’ve downloaded Unity today and tried it out.
However, MonoDevelop isn’t launching for me. I’m not even getting an error message. It’s also not appearing in the task manager.

I tried re-installing Unity multiple times and also re-installed .Net Framework 4.0. Also I’m installing Unity on my external drive, can this be an issue?

Installing Unity (with MonoDevelop) to my Internal HDD, instead of my External HDD, fixed the problem. However I don’t know why it wouldn’t launch externally.

I found that although Unity installs successfully over the previous version, I had to explicitly delete the MonoDevelop directory before upgrading.