Microsoft Forms: why "Anyone can respond" is greyed out

"Anyone can respond" is greyed out when the form has a file upload question, because Microsoft allows file uploads only with "Only people in my organization can respond" or "Specific people in my organization can respond". Delete the upload question, then pick Anyone can respond. If there is no upload question, your admin may have turned off external sharing for Forms. Exact names may differ on your screen.

What the setting does

In Microsoft Forms you open your form and select Collect responses. Microsoft's help page says: "Select Collect responses to display options for sending your form." There you choose who can answer. Microsoft's page describes three choices:

Anyone can respond: "Anyone inside or outside of your organization can submit responses to your form or quiz."
Only people in my organization can respond: "Only people within your organization, signed in with a work or school account, can submit responses."
Specific people in my organization can respond: "Only people or groups in your organization that you specify can respond to your form or quiz."

The same page says the two organization options are only available for Office 365 Education and Microsoft 365 Apps for business users. Our reading, not a Microsoft rule: with another account type, the list you see may be shorter.

Signs this is your problem

You open Collect responses and the Anyone can respond choice is grey and cannot be selected.
The form has a question where people attach a document or a photo.
Customers, parents or contractors outside your company are asked to sign in, or cannot open the form at all.
A coworker's form works for outside people but yours does not.

Cause 1. The form has a file upload question

Microsoft's help page for file upload questions says: "File upload is only available when 'Only people in my organization can respond' or 'Specific people in my organization can respond' is the selected setting." So a form with a file upload question belongs to the two organization settings. It cannot be open to anyone.

A Microsoft Q&A answer to a person with this exact problem says the same. It says the option is disabled when a file upload question exists, and its first suggestion is to remove all file upload questions from the form and then select Anyone can respond.

How to check and fix:

Open https://forms.office.com and open your form.
Scroll through every question. Look for the ones that ask people to upload a file or a picture.
Decide whether the form needs the files. If it does not, delete each of those questions.
Select Collect responses.
Select Anyone can respond.

If the choice is now available, cause 1 was your problem.

Before you delete a question, think about the data. Deleting a question removes it from the form. Responses that were already collected may no longer show an answer for it. Our advice, not a Microsoft rule: export your existing responses to a spreadsheet first, so you keep a copy.

File upload limits

Microsoft's page on file upload questions says: "A maximum of 10 files is allowed to be uploaded per question." It also lets you choose a maximum file size of 10MB, 100MB, or 1GB per question. It adds that "File upload questions are not available for personal forms when Microsoft Information Barrier is enabled." If those limits do not fit your case, you need a different way to collect files, covered in the next section.

If you need the files, keep the form and change how files arrive

Sometimes you do need documents from outside people. The form cannot do both at once. One way to start is to remove the upload question and ask people to send files another way, such as a file request link placed in the form description. The Microsoft Q&A answer suggests a OneDrive or SharePoint file request link as a workaround. That route has its own admin requirements. I wrote a separate guide on it: "Microsoft Forms file upload is greyed out for outside people". This page stays on the greyed-out setting itself.

If you removed every file upload question and Anyone can respond is still greyed out, the Microsoft Q&A answer says the cause is that "your organization's Microsoft 365 admin has disabled external sharing for Microsoft Forms at the tenant level."

Microsoft's admin page for Forms describes this setting. It says an administrator can control whether people outside your organization can work with your forms, and it lists sending "a link to the form to people outside of your organization" and collecting responses as one example. The setting is called External sharing. The page says it has four options, all checked by default, and an admin can uncheck the ones the company does not want.

This is an admin choice. You cannot change it from your own form. What to do:

Tell your admin which form it is and who needs to answer it.
Say the exact problem: "Anyone can respond is greyed out, and the form has no file upload question."
Point your admin to the Microsoft page listed under SOURCES, "Administrator settings for Microsoft Forms". The setting is at https://admin.microsoft.com/#/Settings/Services. Microsoft's admin page says to select Settings, then Org settings, then Microsoft Forms. The checkbox is named "Send a link to the form and collect responses" in the External sharing section.
Let your admin decide. Letting outside people answer forms is a security choice, and some companies keep it off on purpose.

Microsoft's admin page also notes that the option named "Send a link to the form and collect responses" must stay checked if people want to create polls in Outlook. That tells you the same option is used by more than one feature.

Anyone can respond is not the same as anonymous

Microsoft's page says Anyone can respond means "These responses do not require someone to sign in." The same page says "You can choose to have their name recorded or not." For people inside your company, the admin center has a setting called Record names by default, under Record names of people in your org. Microsoft's admin page describes it as a way to capture names of form responders.

Quick way to tell the two causes apart

Open the form and look for any file upload question.
If there is one, it is cause 1. Remove it and try again.
If there is none, it is probably cause 2. Ask your admin.
Not sure? Make a new blank test form with one simple question. Open Collect responses. If Anyone can respond is also greyed out there, the block is not your form. It is a setting your admin controls.

What to avoid

Do not keep the file upload question and keep looking for a hidden switch. Microsoft's page ties that question to the two organization settings.
Do not delete questions without saving a copy of your responses first.
Do not ask your admin to turn off outside sharing limits for the whole company just for one form. Describe the form and let your admin choose the smallest change.
Do not copy an old link to a different form and assume it behaves the same. Each form has its own audience setting.
Do not collect sensitive details on a form that anyone can open without signing in. People do not have to prove who they are.
Do not use a personal account to work around a company block. Ask first.

Honest limits

Microsoft's pages do not describe a way to allow file uploads from people who are not signed in. They also do not describe a way to turn on Anyone can respond for a single form when the admin has blocked external sharing. If you are at a school or company, those choices sit with your admin. If your form only needs short text answers, choices and dates, you can open it to anyone once the upload question is gone and your admin allows it.

If you want to keep one answer per person on a form that anyone can open, see "Stop people filling in a Microsoft Form more than once" for what changes when sign-in is not required.

When to get help

You can build all of this yourself in Microsoft 365. If you would rather have it built and tested for your team, I do that. A tracker like this is a fixed price: $5,000 for one, built in 2 weeks. See "What a SharePoint tracker costs to build". Bring one example of the problem to a free call.

Tell me what's still manual

I am Al Davies. I run 250 High Street LLC and build SharePoint trackers and Power Automate flows for operations teams. I work remotely. The first call is free, and I will not try to sell you anything.

See trackers I built: Tools I built

FAQ

How do I enable Anyone can respond in Microsoft Forms?

Open Collect responses and select Anyone can respond. If it is greyed out, remove any file upload question first.

Why is Anyone can respond greyed out, or not working?

The form has a file upload question, which Microsoft ties to the two organization-only settings, or your admin turned off the external sharing checkbox for Forms.

Is Anyone can respond anonymous?

Microsoft's page says these responses "do not require someone to sign in", and that you can choose whether names are recorded.

I removed the upload question and it is still greyed out. What now?

Ask your admin about the External sharing setting "Send a link to the form and collect responses" in the Microsoft 365 admin center.

How many files can a form upload question take?

Microsoft's page says a maximum of 10 files per question, with a per-file size you choose of 10MB, 100MB, or 1GB.