I’m sorry, I know this is incredibly basic… but I haven’t touched unreal in a few years. There’s an old project file I need to open, now, but I can’t remember, for the life of me, how to do it. Double-clicking the project file tells me that it needs to rebuild two files-- which it then fails to do, telling me to rebuild from the source. Any ideas?
I would recommend telling me that I am a bigger noob then you. You need to work out what engine version you were originally using for that project and then try to open the project using that. You can remove those two files from your project then open it. The last option you could do is get the latest engine version and move all the files using explorer in to that project.
This sounds like you need to open the project in an IDE first to build the missing pieces.
Right click your .uproject file and select “Generate Visual Studio files”, or if you’re on a Mac “Generate Xcode Project” or if you’re on Linux I believe it’s “Generate Project Files”.
After this is done, on Windows you should have a .sln file. Double click it to open it and it will open in Visual Studio. Make sure you have the Community 2015 edition installed. If you’re on Mac, double click the .xcworkspace file and it’ll open in Xcode. You’ll need Xcode installed. If you’re on Linux, then I suggest using the .workspace file with Codelite. You’ll need Codelite installed first.
Then select build. In Visual Studio this button should be on the upper bar (build solution). In Xcode, hit the Play button or select Product > Run. In Codelite, on the left, right-click the game module that ends with the word ‘editor’ (e.g MyProjectEditor). Select build.
This should build the files your project needs to run. Once this is done, you should be able to open your .uproject file like normal by double clicking, assuming the build process was successful.
It will help you and others if you first know what it is that is failing to build. Is it a plugin? Is it the game module? Or is it a C++ file or files? Hopefully some of this information is helpful to you in one way or another.