Error when I try to upload or delete files

For the last few weeks I have not been able to either upload new files to the “Page media” section or delete existing ones from there in the Admin Toolkit. Until recently, this worked without a problem.

I can - of course - still add or remove these files using the file-explorer on the server, directly adding or deleting the files in the file-system. However, the idea is that users can edit this content who have an account for the Grav Admin Webpage but are not authorized to connect to the server using remote desktop.

My user has the following roles: “admin.super”, “admin.login” and “site.login”.

The error messages are the following:

  • trying to upload a file name “test.json”, the error is “Unable to upload file test.json: Bad filename”. There are absolutely no dangerous characters in the filename, so I don’t think that is the real problem.
  • trying to delete a file, the error is “No file found” appearing in a red snackbar. But as the file is shown in the “Page Media” section (and as I can confirm from the file-system), the file does exist.

I set the access-rights to the grav folder to “full control” for the “Users” group.
(And I am running a Windows server).

Any ideas or suggestions would be greatly appreciated.

Small update: This seems to happen only with json Files: If I rename my test.json to test.pdf without changing the content, it works just fine.