Authentication Issues

Authentication problems are among the most common issues people encounter with video downloaders. You can see the video in your browser just fine, but Fetchii says you need to log in. This guide will help you fix that disconnect.

Understanding the Problem

When you watch a video in your browser while logged in, your browser sends cookies that prove your identity to the website. Fetchii doesn't have access to those cookies by default, so it appears to the website as a stranger who hasn't logged in. The solution is always the same: give Fetchii access to your logged-in session.

When this happens, the download's row turns red with a lock and a message such as "Login required", "Age restricted" or "Login may help", and a Resolve… button stays visible. Click it to see your options.

The Easiest Fix: Browser Extension

The Fetchii browser extension creates a direct link between your browser sessions and Fetchii. When you download via the extension, it automatically sends your current login cookies along with the download request.

Here's the workflow: Go to the video you want to download in your browser, make sure you're logged in and can actually watch it, then right-click and select Download with Fetchii. Your cookies are sent automatically with the request. Now Fetchii can download as if it were you.

For a download that already failed, click Resolve… and then Retry with Extension (also in the row's right-click menu). Fetchii asks the extension for your current cookies and retries; the row shows "Waiting for Browser Extension…" and then "Retrying download…". Open in Browser opens the video's page if you need to log in first.

If the extension isn't installed yet, the same sheet offers Set up browser extension, which takes you to Settings → Browser Extension.

When the Extension Isn't Working

If the extension approach isn't an option — maybe you're using an unsupported browser, or the extension isn't connecting — Fetchii can read cookies directly from a browser instead.

In the Resolve… sheet, the Auto Import from Browser option has quick-retry buttons for Firefox and Google Chrome. Click the browser you're logged in with, and Fetchii retries the download with that browser's cookies. Chrome asks for permission first (see below).

This handles two-factor authentication naturally, since you logged in through your real browser.

To have Fetchii always use a browser's sign-in, go to Fetchii → Settings → Advanced → Signed-In Sites and choose a browser under Use sign-in from. The menu lists the supported browsers installed on your Mac: Firefox, Google Chrome, Brave, Microsoft Edge and Chromium. Safari isn't supported.

Firefox is recommended as it doesn't require extra permissions. Chrome and the other Chromium-based browsers work too, but macOS may ask you to allow Fetchii in System Settings → Privacy & Security → Full Disk Access and to approve a Keychain prompt. Settings shows whether access is working.

This approach reads cookies from your browser each time you download, so you still need to log into websites in your browser first. Fetchii doesn't keep its own copy of these cookies. Downloads sent from the browser extension carry their own sign-in and don't need this setting.

Site-Specific Guidance

Different sites have different quirks. Here's what to know for the most popular ones:

YouTube

Private videos require that the video owner has specifically shared it with your Google account. Verify you can watch it in your browser while logged into the correct account, then retry with the extension or your browser's cookies.

Age-restricted videos require completing YouTube's age verification in your browser first. Once verified, retry and you're good to go.

Premium content (ad-free, 4K, etc.) requires an active YouTube Premium subscription. The Premium features travel with your logged-in session, so your cookies give Fetchii the same access.

Vimeo

Private videos may require either an account login or a video-specific password. If it's password-protected, paste the link into Fetchii (1.1.2 or later), click Enter Password… on the row that says Password required, and type the password the owner gave you.

On-demand content requires you to have purchased or rented the video. Your purchase is tied to your Vimeo account, so use that account's cookies.

X

Private posts with media require you to be following the account (or have other access). Log in to the correct X account, verify you can see the post, then download through the extension.

Cookies don't last forever. Sites periodically expire sessions for security reasons, meaning cookies that worked last week might not work today.

If downloads that used to work start failing with authentication errors, the first thing to try is logging into the site again in your browser and retrying the download. The extension sends fresh cookies with each download request, and Use sign-in from reads them fresh each time. Most of the time, this is all that's needed.

Cookies the extension sends are kept only for a limited time — 7 days by default. You can change this under Settings → Browser Extension → Cookies from Browser Extension → Cookie retention.

Two-Factor Authentication

If a site uses 2FA (two-factor authentication), you need to complete the full login process including 2FA before your cookies are valid.

The browser extension and Use sign-in from both handle this naturally — you log in through your actual browser, complete 2FA normally, and Fetchii uses that authenticated session.

Multiple Accounts

If you have multiple accounts on a platform (personal and work, for example), make sure you're logged into the right one before you download. Fetchii uses whatever session is currently active in your browser.

When switching between accounts, download again through the extension so Fetchii gets the new account's cookies. The old session won't automatically update to the new account.

When Your Session Gets Invalidated

Certain actions force you to log in again everywhere:

Changing your password
Using a "sign out of all sessions" security feature
Triggering security alerts by logging in from unusual locations
Account security settings that limit session duration

If downloads suddenly stop working after any of these, you just need to log in again in your browser and retry.

Where Fetchii Stores Cookies

Cookies sent by the browser extension are stored locally on your Mac at:

~/Library/Application Support/Fetchii/cookies/

They're encrypted, used only for the site they belong to, and never uploaded anywhere. To see or remove them, go to Settings → Browser Extension → Cookies from Browser Extension: Stored browser cookies lists each site with a delete button, and Clear All Cookies removes everything.

If Nothing Works

Before reaching out for help, run through this checklist:

Can you watch the video in your browser? If no, fix that first — Fetchii can't download what you can't access.
Are you logged into the correct account? If the video is shared with your work account but you're logged into your personal one, retrying won't help.
Is the extension connected? Click Test Connection in Settings → Browser Extension.
Is the extension enabled? Check your browser's extension settings.
Did you retry with fresh cookies? Old cookies might have expired — log in again and use Retry with Extension.
Did you try your browser's cookies? Use sign-in from sometimes works when the extension doesn't.

If you've checked everything and still can't get authenticated downloads to work, select the failed download and use Report Issue… in the inspector or the row's right-click menu, or choose Help → Report a Problem…. Mention which site, which browser and which authentication method you tried; Copy Error gives you the exact error text. This helps narrow down the issue much faster.