The error is launched by the imagemin task, which is responsible for compressing the images of the project.
Have you added or deleted any images lately?
In any case, check in Gruntfile
the configuration of imagemin to verify that the path where you save the images as well as the formats you use are included.
If you used yeoman to generate the project you can use the variables yeoman.app and yeoman.dist to define the routes, if you can not put the routes at hand as 'dist / images'
imagemin: {
dist: {
files: [{
expand: true,
cwd: '<%= yeoman.app %>/images',
src: '{,*/}*.{png,jpg,jpeg,gif}',
dest: '<%= yeoman.dist %>/images'
}]
}
},
src: '{,*/}*.{png,jpg,jpeg,gif}',
should select all images png, jpg, jpeg and gif from the images directory of your app and save them in dist / images.
Another alternative is to go through the entire project looking for images instead of placing them in the images folder with:
cwd: '<%= yeoman.app %>',
src: ['**/*.{png,jpg,jpeg,gif}'],