I've just come across this post because I was wondering why my project is not opening and I am receiving an error message about the file type. I viewed the console and couldn't make sense of what the problem was. I did change the file name/type from ".c3p" to ".zip", extracted - then confirm if the file had the correct image and it was confirmed to me. I was not readily aware of the "exact" problem until I seen this post. So I closed out the spaces in the image name and made the corrections.

However, When I changed it back to .c3p, it proceeded to show me another error in the console. Fixed it again, compress, extract etc and THEN it showed me another error in the console etc. This maybe a problem for alot of the objects I have in my game.

The reality is, that like many of us developers who are so far into development- my game is HUGE! There are a multitude (perhaps) hundreds of objects in the project that could have this issue.

This really is annoying considering that I cannot use it on the current version of construct. Granted, I was able to open the project in r388.2, Though admittedly I would hope they fix this.

To fix it you can do this:

1. Open the project in the current version of construct. Press F12 and check error messages in console log.Important!:This can be the name of a file, event sheet or even the name of an animation (example: button_resume-eng-000.png - here "eng" is the name of the animation)

2. Open the project in the previous release r388.2

3. Go through the Project Bar and make sure nothing has a name that starts or ends with a space. Considering the error you saw in the console log.

4. Save the project

5. Open it again in the current version of construct. If there is one more error, go to step "1". And repeat in a circle until the errors when opening in the current version disappear.

Seems like there is a problem with one of the images - button-resume-eng

I wonder if it's related to these changes.

I suggest you try reproducing this issue in a small project, perhaps copy that sprite to it and try to open in r397. And if you get the same error, file a bug report:

https://github.com/Scirra/Construct-bugs/issues

Thank you very much for helping me!

One problem that has come up in the latest release is that files and folder names that start or end with a space are actually invalid (systems like Windows block creating files with such names), and Construct now enforces this too. However it means existing projects which use invalid names with spaces at the start or end cannot be opened. These projects will have also been unable to be saved as a folder project because of the use of these invalid names, so arguably they were already broken due to the use of invalid names.

To fix it you can do this:

1. Open the project in the previous release r388.2
2. Go through the Project Bar and make sure nothing has a name that starts or ends with a space
3. Save the project
4. Open it again in the latest release r397

If it doesn't open, check the browser console for error messages again, and go through and repeat this process checking for that name in particular.

If you still can't get it to open email your project to supportbll@construct.net and we'll take a look.

Unfortunately projects using invalid names is a really difficult problem and it's very difficult to have Construct automatically deal with this. The important thing is to make sure everything in your project has a valid name, and the latest releases do now correctly validate that, so it shouldn't be possible to happen again. And if you found you were unable to use folder projects, it should work again after doing this.

It is incredibly. That was really the problem. In my particular case, I had a space at the beginning of the names of some animations and the name of one event sheet. I fixed it and now everything works. Thank you very much!

> > "Failed to open project. Check it is a valid Construct 3 single-file (.c3p) project"

>

> When you see this error, press F12 and check the last error messages in the console log.

And when I open this project (or other similar backups) in R388.2 and everything works, there are no errors.

> "Failed to open project. Check it is a valid Construct 3 single-file (.c3p) project"

When you see this error, press F12 and check the last error messages in the console log.

Well, I tried the older version R388.2 and my projects open, but I still can't open them in the newer version of the program. The problem is still there.

I see this error occasionally when double-clicking a c3p file, but it usually works second time around. It feels like C3 hasn't loaded completely so errors trying to load the project. Try opening C3 first, then use the "Open" button.

Does not work. the most important thing is that now when I create a new project, it opens, but hundreds of different versions of projects that have been working for more than two years, none of them opens now, although everything was working 2-3 days ago. And there has never been anything like it. I don't understand what the error is.

This was not the case before. can't open projects. "Failed to open project. Check it is a valid Construct 3 single-file (.c3p) project"