HELP! I broke my project when trying to convert it to C++ and I don't have a backup

Firstly, I don’t really know the best palce to post this.

Secondly, I know, i know, ALWAYS backup. But I didn’t clone my project before attempting to convert it, and the worst part is I’m not even sure I need to convert it, I was just trying to get a JSON query plugin working and now my project won’t even open so bye-bye a few months’ work.

I was following instructions on a post to convert to c++ project because it said it needs to be for a plugin to work, which made me think maybe the json plugin needs that too. It said to create an empty c++ class and then exit the engine and “generate visual studio project files” for the project in windows. When I tried to do that I was met with an error that says “Failed to Generate project files” and prints this:

i have windows sdk 8.1, so i dont understand. And when I try to open my project I am met with this error:

If I choose yes, it fails and responds with “Sidescroller could not be compiled. Try rebuilding from source manually.” Which I would have no clue whatsoever how to do. Is there any way to fix this or have I just ****ed my game?


Here’s my first-ever post in order to help you! =) Several days later; I’m surprised no-one responded to you. You haven’t indicated if you’re using a source-built engine or a prebuilt from the Epic Launcher. This section is for people building the engine from the source-code (available on Github).

The obvious first: months of work and no backup! I see you already understand your mistake, so I’ll instead suggest using source control (such as Git) in the future. Source control will let you go back and review (and revert as needed!) individual changes you have ‘committed’ in the past, without needing to keep and manage full copies as backups.

Next, if you haven’t already: make a backup now (a nice, full duplicate to be safe). You absolutely CAN make it much worse - especially with the suggestions I’m going to give you!

I only use Linux for development, so I cannot help you with getting the JsonQuery plugin to build. That said, it does sound like a dependency issue. The warnings aren’t always helpful. From memory, the engine may expect a very specific SDK sub-version in Windows but I may be wrong.

To recover your work (if it is only Blueprint and you haven’t actually done any C++ work), you can try to manually ‘revert’ it to a Blueprint-only project. You can do this by removing the project “Source” directory (which should only contain the empty class you made) and manually remove the generated modules entry from the “uproject” file (in any plaintext editor - should be one with the project name). The project should then be able to open as a Blueprint-only project just as it did before ‘converting’ it.

If the engine complains about a plugin being out of date, you can try disabling the problem plugin/s. If you’re using a prebuilt engine (which I’d guess you are, despite posting here, given the dependency error you have), perhaps see if someone would be kind enough to provide you with a prebuilt binary of the JsonQuery plugin for your Epic-prebuilt engine version.

Note that you could make everything worse by following my suggestions, so do make that full backup. It’s a bit bodgy, so wouldn’t suggest any of this if someone else more knowledgeable about Windows issues replied, but no-one else has. This should at least get you to where you were prior to trying to enable the JsonQuery plugin.

Good luck!