id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
35674	Provide a check for `DEFAULT_FILE_STORAGE`	Serafeim Papastefanos		"Hello friends, I had a `DEFAULT_FILE_STORAGE = ""storages.backends.s3.S3Storage""` in my Django 5.0.8 project. When I upgraded it the project worked but the user-uploaded content was uploaded to the filesystem instead of S3. This happened because my `DEFAULT_FILE_STORAGE` setting was ignored so it fall back to the STORAGES default (https://docs.djangoproject.com/en/5.0/ref/settings/#storages): 



{{{
{
    ""default"": {
        ""BACKEND"": ""django.core.files.storage.FileSystemStorage"",
    },
    ""staticfiles"": {
        ""BACKEND"": ""django.contrib.staticfiles.storage.StaticFilesStorage"",
    },
}
}}}



I know that the release notes mention that these settings are removed but since I fell for it there may be also other users that experience the same problems.

My recommendation is to provide a patch in 5.1 that uses the checks framewortk (https://docs.djangoproject.com/en/5.0/topics/checks/) to make sure that there is no  `DEFAULT_FILE_STORAGE` (and probably a `STATICFILES_STORAGE`) setting and do not allow starting the project unless the user fixes it.
"	New feature	new	Error reporting	5.1	Normal				Unreviewed	0	0	0	0	1	0