Bolt not installing properly (deprecated code, lots of warnings/errors)

I do all my coding in C#, but with Unity's recent acquisition of Bolt, I decided I'd give it a chance, considering it might help me prototype basic ideas much quicker on the fly before I commit to coding something. I'm having tons of trouble installing Bolt though. I'm using Unity 2020.1.0a18.2166 and the latest version of Bolt 1.4.12.

After I import it into my new, empty project, I'm hit with about 15 warnings all along the lines of obsolete code:

Code (CSharp):

1. Assets\Install Bolt\Editor\InstallBoltMenuItem.cs(51,9): warning CS0618: 'ScriptingRuntimeVersion' is obsolete: 'ScriptingRuntimeVersion has been deprecated in 2019.3 now that legacy mono has been removed'

Then when I attempt to install Bolt by going to Tools > Install, I run into an error ...

Code (CSharp):

1. System.TypeInitializationException: The type initializer for 'Ludiq.BackgroundWorker' threw an exception. ---> Ludiq.UnityEditorInternalException: An error occured while accessing internal Unity Editor functions. This might happen if Unity makes backward-incompatible changes in their newer versions of the editor. ---> System.ArgumentNullException: Value cannot be null.
2. Parameter name: types

And a bunch of warnings about Bolt using a "legacy pdb format"

Code (CSharp):

1. Unity is only able to load mdb or portable-pdb symbols. Assets/Ludiq/Assemblies/Bolt.Flow.Runtime.pdb is using a legacy pdb format.
2. UnityEngine.Debug:LogWarning(Object)
3. Microsoft.Unity.VisualStudio.Editor.VisualStudioEditor:SyncIfNeeded(String[], String[], String[], String[], String[]) (at Library/PackageCache/com.unity.ide.visualstudio@2.0.0/Editor/VisualStudioEditor.cs:119)
4. UnityEditor.AssetPostprocessingInternal:PostprocessAllAssets(String[], String[], String[], String[], String[])

Then when I run the setup wizard (Tools > Bolt > Setup Wizard), the bolt window that pops up goes goes completely black for the naming conventions step, with no choice but to exit out of it.

Considering these warnings and errors, it sounds like Bolt is using a lot of deprecated code and functions, but I'm using the most recent release of Bolt from May 4, 2020, and a very recent version of Unity. It seems no one else is having these errors either, so I must be doing something wrong, but this is a new blank project and immediately importing Bolt. Any advice? Thanks!

 

It looks like you're using an alpha version of Unity - have you tried using a recent version from the official release channel? Not that it's definitely the problem, but worth a shot.

 

Thanks for the suggestion, I just attempted to import into 2020.1.0f1 and unfortunately, same warnings and errors. I also tried 2019.3.0a5 and importing through the asset store instead of package manager, but I still get deprecated warnings (not sure how much of an impact they have since they're just warnings):

Assets\Install Bolt\Editor\InstallBoltMenuItem.cs(76,80): warning CS0618: 'ScriptingRuntimeVersion' is obsolete: 'ScriptingRuntimeVersion has been deprecated in 2019.3 now that legacy mono has been removed'

And about 10 new errors which are all seem to be related, about dll's not being loaded:

Assembly 'Assets/Ludiq/Assemblies/Bolt.Flow.Runtime.dll' will not be loaded due to errors:
Unable to resolve reference 'UnityEngine.UI'. Is the assembly missing or incompatible with the current platform?
Reference validation can be disabled in the Plugin Inspector.

I've tried a handful of other random things, like installing the NET3 package instead of NET4, and resetting Unity to the default UI and settings, etc. Nothing seems to work, sadly

 

Just an update for others who run into this problem. Unfortunately, I wasn't able to resolve the issue in a completely simple way. I ended up having to do a complete uninstall of Unity and Unity Hub (removing all the AppData folders, simply uninstalling wasn't enough), then redownloading and reinstalling. It'll definitely bother me that I never understood what was causing the error, but at least I know what to do if it ever pops back up!

side note - After trying out Bolt for awhile, I decided I'll remain using C# for prototyping - it could be that I was still finding my way around Bolt, but most simple prototyping tasks I can lay out much quicker in code. Personal preference I suppose. I can definitely see the appeal of visual scripting though... a lot more user-friendly and being able to edit your graphs in play mode is amazing!

 

Unity Bolt Setup Wizard won’t work
it won't finish