FAQ

Troubleshooting download failures

Download failures usually come down to one of four causes. First match the error message to one of the categories below, then follow the fix in the matching section:

Cause	Typical symptom	Jump to
Network or proxy issues	Resolution fails after switching to a company or campus network	Cause 1
Site risk control (human verification)	A message like "we cannot verify this visit right now" or a suspected-bot warning	Cause 2
Site rate limiting	Sudden speed drops or frequent failures across multiple tasks	Cause 3
Content requires login	A prompt asking you to log in, or an incomplete quality list	Cause 4

Cause 1: Network or proxy issues

Typical symptom: resolution fails after changing network environments (company network, campus network), or it just keeps spinning with no result.

How to fix it: open Settings → Network and adjust the proxy configuration —

• If the default system proxy doesn't work, try switching to no proxy and connect directly;
• On a corporate intranet, follow your IT department's instructions and choose manual setup, then enter the proxy address.

Cause 2: Site risk control (human verification)

Typical symptom: a message saying the site cannot verify this visit right now, or a suspected-bot warning.

How to fix it (try these in order):

1. Click Log in via browser in the prompt, pick a browser that is already signed in to the site, and retry;
2. Change your network environment (e.g. switch to a mobile hotspot) and try again;
3. Wait a while and download again later.

Cause 3: Site rate limiting

Typical symptom: download speed suddenly slows down, or multiple tasks fail frequently at the same time.

How to fix it (try these in order):

1. In Settings → General → Transfer tasks, lower the maximum number of simultaneous downloads;
2. Turn on speed-limited downloads to give the site some breathing room;
3. Pause for a while, then resume.

Cause 4: Content requires login

Typical symptom: a prompt asking you to log in, or resolution succeeds but the quality list is incomplete.

How to fix it: simply log in to the site. See Login and cookies below.

Playback issues

• Video plays audio only, with no picture? (Fedora) This isn't an app bug: for patent reasons, the official Fedora repositories don't provide an H.264 decoder, and the default noopenh264 package is only a placeholder stub that can't actually decode. Enable the fedora-cisco-openh264 repository and install openh264 to fix it. For the full steps, see the Linux installation guide. Ubuntu / Debian are not affected.

Supported websites

• Which websites does aividlab support? Over 1,800 video websites. Popular sites such as Bilibili, Douyin, Kuaishou, Xiaohongshu, YouTube, and TikTok are fully tested and safe to use. Less common sites haven't been tested one by one, so if you hit a resolution or download problem, feel free to report it in the community group — we keep adding support over time.

• A website fails to resolve — is it the app's fault? Not necessarily: site redesigns, site risk control, and network conditions can all cause failures. Try again once, switch networks, or log in and retry. If it still fails, post the video link in the community group along with the error message, and we'll look into it.

Login and cookies

First, understand: how do cookies work?

Many sites require a logged-in state to access their videos: once you log in, the browser stores a set of "login credentials" locally — that's the cookie. By reusing those credentials, aividlab can resolve and download this content on your behalf. The credentials stay on your own computer and are never uploaded.

There are three ways to provide credentials, switchable under Settings → General → Cookie source:

Method	Best for	Notes
System browser (recommended)	People who normally log in to video sites with Chrome / Edge / Firefox	Reuses the browser's existing login — no re-login needed, and expired sessions update automatically with the browser
Built-in browser	People who don't want to log in via the system browser, or are on a shared computer	Log in inside aividlab's built-in window; the login state is only used by aividlab
Cookie file	When the first two methods fail to read credentials	Export a cookies.txt file with a browser extension and import it — the most reliable option

Common questions for each method are covered below.

Why is "System browser" recommended?

aividlab uses the login state already in your browser: there's no need to log in again inside the app. Whichever account you're signed into in the browser is the one aividlab uses, and expired sessions update automatically along with the browser — the most hassle-free option.

What if Chrome can't be read (especially on Windows)?

Newer versions of Chrome / Edge encrypt local login information more strongly, and on some computers it can't be read directly. Try these steps in order:

1. Switch to a Firefox profile that's already logged in;
2. Make sure Chrome has fully quit (all windows closed) and retry;
3. Import via a cookies.txt file instead (see the next section).

A "failed to read browser login info" message appears?

The most common cause is that the selected browser is still running. Fully quit that browser (close all windows, and quit it completely from the taskbar / dock if needed) and retry. If it still doesn't work, switch to another browser, or use the cookie file method instead.

How do I import cookies.txt?

1. Install the Get cookies.txt LOCALLY extension in your browser (available in both the Chrome and Edge stores);
2. Open the target video site and make sure you're logged in;
3. Click the extension icon and choose Export to save the file;
4. In Settings → General → Cookie source, choose Cookie file and select the exported file.

For illustrated step-by-step instructions, see the video download guide.

A "login expired" message appears?

Log in to the site again in your system browser first, then go back to aividlab and retry. You can also clear that site's login state in the "Browsers" panel and log in again.