Once unpublished, any user that clicks an inactive form link would receive a 404 error message. ... If you don't enter a message, Google will use the default message: “This form [title of form] is no longer accepting responses. Try contacting the owner of the form if you think this is a mistake.”
Four 'Not-So-Obvious' Tips to Use Google Forms Like a Pro
uit.stanford.edu > blog > four-‘not-so-obvious’-tips-use-google-forms-pro
Fix file upload settings. This form supports file uploads and is limited to collect undefined B of files. The file upload limit has been reached, and so this form is no longer accepting responses. Edit your form settings to increase the upload limit or delete files to continue accepting responses.
The Google Form is no longer accepting responses. Fix file upload ...
support.google.com > docs > thread > the-google-form-is-no-longer-accept...
Late work submission (with email notifications!) ... You can receive an email when they submit the late work form. In Forms, use the “Responses” tab and click the three dots menu button. Select “Get email notifications for new responses”.
25 practical ways to use Google Forms in class, school
ditchthattextbook.com > 20-practical-ways-to-use-google-forms-in-class-sc...
(Optional) Do any of the following actions:
1. Specify which file types people can upload. Next to Allow only specific file types, click Turn on and select the types.
2. Change the maximum number of files that people can upload.
3. Change the maximum file size.
4. Set a maximum size for all files collected via the form.
Get attachments from form respondents - Google Workspace ... support.google.com > users > answer