Strange issue with blueprint after reinstalling UE4.. Any suggestions?

I recently made the jump from Win7 to Win10, and of course had to reinstall UE4 in the process.
Once I had done so, (and taken care of Visual Studio etc) I then fired up the project I was working on before the re-install and much to my surprise one of the core blueprints wasn’t working properly, when it certainly was before and hadn’t been touched.

Spent a lot of time trying to figure out what was wrong, and started dropping in some “Print Strings” at various points to try and figure it out…

Turns out making a change to the BP after editor restart fixes the problem - At least for that editor session…
Once the editor is restarted the issue is there again.
The “Change” I make is to simply duplicate a node in the bp and replace the existing one with it… Works fine…
So the Blueprint is identical… But must go through replacing a node every time I restart the editor…

Anyone else had similar issues? Any suggestions/help much appreciated- This is driving me nuts :slight_smile:

(Not that I think it matters but the node that always “fixes” it when replaced is a drag and drop operation node… If I don’t replace it, the variables it passes are none/null)

Ok… So after posting this I managed to resolve the issue… (I think!)

Anyone else having similar strange blueprint behaviour after reinstalling UE4, I would highly suggest recompiling ALL blueprints.
They may have a pretty little green check, but all was not well until after recompiling everything! :slight_smile:

I can breathe a sigh of relief now… (Once I finish kicking myself)