ChatGPT says “File Not Found” or the file expired: how to get your file

When a file link in ChatGPT shows “Download failed” or “File Not Found”, OpenAI’s help center tells you to check that “the file is recently generated,” because “files generated by ChatGPT expire quickly.” Look for the file in Library on the web first. If it isn't there, ask ChatGPT to make the file again, and download it as soon as the new link appears. Outside one Enterprise case, OpenAI’s pages, read on November 5, 2026, give no time for how long a file lasts.

This guide is for the moment after you asked ChatGPT for a file, such as a PDF, a spreadsheet, or an HTML page like index.html or dashboard.html, and the link in the chat gave an error, did nothing, or started with sandbox:/mnt/data/. It covers what each of those means, where else the file may be, and what to ask ChatGPT. If the file was a web page, you don't need the file at all: the code is enough to see the page and to publish it.

Why the download link stopped working

OpenAI’s troubleshooting page names the two messages together, “Download failed” / “File Not Found”, as “An error that occurs when attempting to download files / click on file links generated by ChatGPT.” It gives 4 things to check:

• The file’s age. “Ensure that the file is recently generated, files generated by ChatGPT expire quickly.”
• A VPN or a proxy. “Disable VPNs or proxy connections.”
• The file’s size. “Ensure the file downloaded is less than the file size limit of 512 MB.”
• A custom GPT’s settings. In a custom GPT, “ensure that 'Code Interpreter' functionality is enabled”. OpenAI’s GPT troubleshooting page adds that “Some download failures are generic file-link errors, so the issue is not always the GPT configuration itself.”

OpenAI doesn't rank the 4 or say how long “quickly” is. Its retention page gives a number for one case only: “For Enterprise workspaces, some transient files can expire after 48 hours unless another retention period applies.” The chat itself stays: regular and archived chats “remain saved to your account until you delete them or an applicable workspace retention policy removes them.”

The file may also be in Library. OpenAI’s Library help says: “The files you upload to and create in ChatGPT are saved to your Library, so you can find and reuse them later. Library is available on web”. Its examples are “documents, spreadsheets, presentations, and images”. It doesn't say whether a file whose link in the chat has expired is still there, and we didn't check: we used no ChatGPT account for this guide.

What you see, and what to do

Our sandbox: test, on November 5, 2026, in Playwright’s Chromium 156, WebKit 27.2, and Firefox 157: opened as an address, sandbox:/mnt/data/index.html failed in all 3 (Firefox called it an unknown protocol), and a link to it on a web page did nothing when clicked. Sent to someone else or pasted into a browser, a link like this opens nothing.

Get the file again

1. Look in Library first. On the web, open Library from the left-hand sidebar. OpenAI says you can “browse uploaded and generated files in one place,” and filter for generated files. To save one, select it and click Download. If your account shows Space instead, OpenAI says “Space takes the place of Library.” Search in the sidebar finds files too, on the web, iOS, and Android, but OpenAI’s search help says you “manage, reuse, download, and delete them from Library or Space.”

2. Ask for the file again in the same chat. For example:

   Copy code

   The download link says "File Not Found". Please create the file again and give me a new download link.
   

3. Download it right away. OpenAI gives no time, only “quickly”, so click the new link as soon as it appears.

4. If it still fails, turn off a VPN or proxy and keep the file under 512 MB. In a custom GPT you built, check that Code Interpreter & Data Analysis is on in its settings, as OpenAI’s GPT help names it. In someone else’s GPT, try the same request in a regular chat. OpenAI’s GPT help also says custom GPTs are being retired: “Standard retirement is scheduled for December 11, 2026.”

We didn't use ChatGPT for these steps. They come from OpenAI’s pages as read on November 5, 2026, and the labels in your ChatGPT may differ: OpenAI says “Available actions vary by plan, device, workspace settings, model, and rollout.”

Open an HTML page from ChatGPT without the file, in 4 steps

An HTML page is text. ChatGPT can give it to you as code in the chat instead of as a file, and OpenAI says a regular chat stays saved to your account until you delete it. This works the same on a phone and a computer.

1. Ask for the code instead of a link

In the same chat, paste:

Don't give me a download link. Show the whole page (the index.html you made) as HTML in one code block, from <!DOCTYPE html> to </html>, with the CSS and JavaScript inside it.

Change index.html to the name in your broken link, such as dashboard.html. If ChatGPT splits the page into several files, ask again for one.

2. Copy the whole code block

OpenAI’s code block help says “ChatGPT usually places code in a code block,” and copying the code is one of a block’s actions. Copy everything from <!DOCTYPE html> to </html>. A page cut off halfway shows up broken.

3. Paste it into the HTML viewer

Open Convika’s free HTML viewer in your browser and choose Paste code. Paste the code and click Show the page. You don't need an account, and the code stays in your browser.

4. Try the page, then keep the code

Click the buttons and tabs. Switch the width to Phone to see it at a phone’s size. The page lasts only while the viewer is open, so keep the code: save it as a file (how to make an HTML file on your phone), or publish it, as the next section says.

On November 5, 2026, we pasted a one-file sales dashboard, with its CSS and a script that draws bars, into the viewer in Playwright’s Chromium 156 at 1280 × 900 and in its WebKit 27.2 at an iPhone 15’s size. In both, the script ran, the bars drew, and a button added more. What runs in the viewer and what doesn't, such as pop-up boxes, is in how to run HTML code from ChatGPT, Claude, or Gemini. Inside ChatGPT, OpenAI says “For supported code blocks, select Preview to view the result inside ChatGPT,” and HTML pages are one kind. If you were looking for ChatGPT’s canvas, see where ChatGPT canvas went.

Keep the page at a link that stays the same

ChatGPT’s download links expire, and so does the viewer’s quick link: Get a link by uploading this page gives a private link that works for 3 minutes, with scripts and forms off. A page you publish keeps one URL until you unpublish it, with its scripts running, and Convika’s Free plan publishes it with no card. What each kind of ChatGPT link is, and the steps to publish, start at Why the ChatGPT link to your HTML file is not working. The free HTML publishing tool starts from pasted code too.

Frequently asked questions

How long does ChatGPT keep the files it makes?

OpenAI doesn't give a time. Its troubleshooting page says “files generated by ChatGPT expire quickly,” so a download link in a chat can stop working while the chat itself stays. For Enterprise workspaces only, OpenAI’s retention page says “some transient files can expire after 48 hours unless another retention period applies.” OpenAI’s Library help says files you create in ChatGPT are saved to Library, on the web, where you can download them.

Why does ChatGPT say “File Not Found”?

OpenAI lists “Download failed” and “File Not Found” as errors on file links ChatGPT generated, with 4 checks: the file is recent, because “files generated by ChatGPT expire quickly”; no VPN or proxy; under 512 MB; and, in a custom GPT, Code Interpreter on. Ask ChatGPT to make the file again and download it at once, or look for it in Library on the web.

How do I download a file from ChatGPT on iPhone?

OpenAI’s iOS and Android app FAQ doesn't say, and we didn't test the app. OpenAI says Library, where you download saved files, “is available on web.” For an HTML page, skip the download: ask ChatGPT for the code in one code block, copy it, and paste it into an HTML viewer in Safari. In our test in Playwright’s WebKit at an iPhone 15’s size, the pasted page’s script ran; we didn't test a physical iPhone.

What is a sandbox:/mnt/data link in ChatGPT?

It names a file, such as /mnt/data/index.html, in the environment where ChatGPT ran code for your chat. It isn't a web address, and OpenAI’s help doesn't describe these links. In our test, 3 browsers opened nothing from sandbox:/mnt/data/index.html. Ask ChatGPT for a new download link, or, for an HTML page, for the code in one code block.

Why did my ChatGPT file expire so fast?

OpenAI says only that “files generated by ChatGPT expire quickly,” with no time. On OpenAI’s community forum, people reported a link that failed even when clicked at once (June 26, 2024), and OpenAI’s page lists other checks: a VPN or proxy, a file over 512 MB, or a custom GPT without Code Interpreter. Ask for the file again and download it right away.

Where are the files ChatGPT made saved?

In Library, OpenAI says: “The files you upload to and create in ChatGPT are saved to your Library”. Open Library from the left-hand sidebar on the web, select the file, and click Download. If your account has Space, OpenAI says Space takes the place of Library. Files uploaded in a Temporary Chat, OpenAI adds, aren't saved to Library.

Can I get an expired ChatGPT file back?

Look in Library on the web first. OpenAI doesn't say whether a file whose chat link expired is still there, and we didn't test it. If it isn't, ask ChatGPT in the same chat to create the file again. For an HTML page, ask for the code instead: code in the chat doesn't depend on a download link.

Sources

• Troubleshooting ChatGPT Error Messages (OpenAI) (read November 5, 2026)
• Using Library to manage files in ChatGPT (OpenAI) (read November 5, 2026)
• Chat and file retention in ChatGPT (OpenAI) (read November 5, 2026)
• Finding your chats, projects, and files in ChatGPT (OpenAI) (read November 5, 2026)
• Working with writing blocks and code blocks in ChatGPT (OpenAI) (read November 5, 2026)
• Troubleshooting GPTs (OpenAI) (read November 5, 2026)
• ChatGPT iOS and Android app FAQ (OpenAI) (read November 5, 2026)
• Forum threads, as people's reports, not OpenAI’s: “The code interpreter tool session has expired.” (posts of May 21 and June 26, 2024) and download links for files created on ChatGPT (post of August 8, 2024), OpenAI Developer Community (read November 5, 2026)