No autocompletion in Monodevelop

Using Windows 10, Unity 5.3.2f1 I also have (had) the auto complete problem and it can be VERY frustrating to not have it and to not be able to fix it. See below for what worked in my particular case, but first, Here's what worked for others, but didn't work for me.

1) the Sync option may have worked for older version, but version 5+ doesn't have it.

2) I tried the option : Unity / Edit / Preferences / External Tools / and changed the Monodevelop (built in) to instead Monodevelop (via Browse and going to c:/program files/unity/mondevelop/bin/monodevelop.exe (this seemed to work for many people, but not me). I also checked off the option "add .unityproj's to .sln" since that also worked for people, but again, not for me

3) I tried deleting .sln and .prj files out of the projects directory like someone suggested to no avail.

What did work : Installing .NET over

In Windows, Go to Control Panel / Programs and Features / (then on the left side) Turn window features on and off / and selecting both .NET 3.5 as well as .NET 4.6.
Why I did this.... I happened to hit the RUN button for my script in MonoDevlep and it gave me an error message that .NET 3.5 was not installed (even though I had .NET 4.6 installed) and even though UNITY was able to compile it after exiting MonoDevelop. MonoDevelop Should be able to compile your scripts so if you get an error, it may be the same situation I had and also be tied to the AUTOCOMPLETE not working.
You should also REBOOT after installing .NET just to be sure.

I even installed IIS as I wanted to install it anyway, but I doubt that did anything. HOPE THIS HELPS!

I have the same problem and I solved in Unity menu "Assets > Sync Monodevelop Project"

More info here: http://answers.unity3d.com/questions/416662/mono-develop-lost-autocompletion-and-refactoring.html

Bonjour , ma solution car toutes les autres n'ont pas fonctionnées. Je copie le dossier de monodevelop d'unity 5.2 vers ma version 5.3.2f1. Ensuite l'autocompletion javascript fonctionne. Ci dessous un lien vers le zip de mono 4.0.1.

http://dl.free.fr/g96UIJOx8

Hello , my solution because all the others have not run . I copy the unity 5.2 monodevelop folder to my 5.3.2f1 release. Then javascript autocompletion works . Below is a link to the zip of mono 4.0.1 .

I fixed with this (using Unity 5.6.0f3):

Go in Project > Edit References in MonoDevelop and in the ".Net Assembly" tab just select every library (or, in case, just what you need).

This will also work in case you still looking for answers. http://answers.unity3d.com/questions/208710/autocomplete-not-working-properly-in-monodevelop.html