Troubleshooting problems

This page is for when you encounter a problem with a source or the app.

What are some common errors?

If error-specific instructions didn't help or your error isn't on the list, go through Diagnosis.

Java.lang Exception: Challenge not found

Often Java.lang Exception: Challenge not found will be resolved by force-quitting and reopening Tachiyomi.

Java.lang Exception: Failed to bypass Cloudflare

Java.lang Exception: Failed to bypass Cloudflare means that the source you selected has Cloudflare protection on, refer to the Cloudflare guide to fix it.

Loader not implemented

Loader not implemented means that the respective extension for the manga is not installed. To fix, install the extension for the manga. If it still doesn't work, uninstall then reinstall the extension again.

Value Manga is licensed at data of type java.lang.String cannot be converted to JSONObject

Value Manga is licensed... means that the manga has been licensed and can no longer be read on that source. Try a different source to read the manga.

HTTP error 403

Possible reasons for HTTP error 403:

• The source you selected has Cloudflare protection on, refer to the Cloudflare guide to fix it.
• The source is down, removed the manga or banned your IP. Open
  public
  WebView to check if this is the case.

HTTP error 404

HTTP error 404 probably means that the source is down or removed the manga. Open

public

WebView to check if this is the case.

HTTP error 429 (Too Many Requests)

HTTP error 429 or Too Many Requests means that the source banned your IP address (in most cases it's temporary). We suggest to migrate part of your manga to another source to reduce number of requests to the source.

HTTP error 5xx

HTTP error 5xx like 500, 502 and others are server errors and the source you are trying to access has problems on their side. Open the source in

public

WebView and check if the site is down.

Unable to resolve host / Connection failed

Errors like Unable to resolve host or Connection failed mean that something prevents your connection with the site. Possible reasons: your internet connection is bad, the app doesn't have access to the internet, your ISP have blocked the site, the site is down. Try using different internet connection (switch to Wi-Fi, mobile data or a VPN). Try to enable

more_horiz

More →

settings

Settings →

code

Advanced → DNS over HTTPS.

java.security.cert.CertPathValidatorException / Chain validation failed

java.security.cert.CertPathValidatorException or Chain validation failed means there is a problem with validating source's sertificate.

• Check if the site's certificate have expired. Use an online service for checking SSL certificates. If the certificate have expired, then wait while the site owner will renew it.
• Ensure that you have the right date and time set on your phone.
• Try
  more_horiz
  More →
  settings
  Settings →
  code
  Advanced → Clear cache and Clear cookies.
• Try using different internet connection (switch to Wi-Fi, mobile data or a VPN).
• Try to restart the device.

App not installed

You may encounter App not installed if you're installing an official build over an existing F-Droid build due to differing signatures. Backup your data, uninstall the app, then restore the data in the fresh install.

Attempt to invoke virtual method 'com.hippo.unifile...

Attempt to invoke virtual method 'com.hippo.unifile... error can be caused by a variety of reasons, all to do with storage.

• Most commonly it is caused by full storage, check to see if your device or SD Card is full.
• Check if Tachiyomi has access to the SD card. You can enable it in the android settings for app permissions.
• If you're downloading and this error pops up, that means the app might not be able to access the folder you're trying to download to. This may be because the folder is corrupted or does not exist. Use a file manager to check that the folder(s) exist and every folder in the sequence is available and accessible.
• The drive you're writing to is corrupted. Check using a file manager to see if it is accessible.

Cannot Access SD Card

Cannot Access SD Card error is typically caused by having a file or folder name that is too long. Android's file manager does not support filenames longer than 255 characters. If you know the file or folder name that is the culprit, you can connect your SD card to your computer and shorten it. Otherwise, delete the Tachiyomi downloads folder off of the SD Card.

Diagnosis

• Verify your extensions are up to date (
  explore
  Browse → Extensions, make sure no extensions have an Update button).
• Check if Tachiyomi has an update (
  more_horiz
  More →
  info
  About then click Check for updates).
• Verify that WebView is updated.
• Try opening the manga in
  public
  WebView . If there is a Cloudflare protection, wait for it to load. If there is a CAPTCHA, solve it and see if it helped.
• Change your internet connection (switch to Wi-Fi, mobile data or a VPN, use a "What's my IP" site to confirm your IP has changed), then try again.
• Ask other users to try the action that gives you the error.
• Check if the source is either down, or is having issues in a browser.
• Press the retry button in the middle of your manga page if one exists.
• Try the following at
  more_horiz
  More →
  settings
  Settings →
  code
  Advanced
  • Clear Cache
  • Clear Cookies
  • Clear Database
  • DNS over HTTPS
• If your downloads are getting stuck, try deleting the queue and trying again.
• Force close Tachiyomi and reopen it.

Your issue may have been fixed in the Preview version already, just wait for a new Stable release.

If any of these help, go to it only happens to me. If it's not just you, go to everyone is having this problem.

If none of these help, try asking in our Discord Server (opens new window). State app version, source, manga and chapter with the problem.

It only happens to me

You may be getting a Cloudflare protection, may have been IP-banned, or encountered some other counter-measure that website owners deploy against programs like Tachiyomi. If that is the case, there is probably nothing that can be done about that. Some of them (like Cloudflare) have to be manually solved, some are temporary (IP bans).

Workarounds that can lower chance of it happening again:

• Don't use downloads with the source.
• Have less manga in library from the source.

All of the above are very imprecise and fuzzy rules, because each site has their own, non-public limits and triggers.

Everyone is having this problem

If the site is reachable and fully functional then there may be an issue with the extension or app.

1. Have a look at open issues for the app (opens new window) and/or extensions (opens new window).
2. It may have been fixed already, but not released yet, so look at closed issues (app (opens new window) / extensions (opens new window)) issues as well.
3. If you can't find the issue there, open a new one.

If the site is not reachable or having issues then all you can do is wait for the site to become functional again.

Solving the Cloudflare issue

Please note that WebView is not the same as using your browser.

You must solve the Cloudflare issue in WebView.

How to open WebView

1. Go to
   explore
   Browse in the bottom navbar.
2. Press the source you'd like to access.
3. Press the
   public
   WebView icon.

   

4. Complete CAPTCHA if one is present.
5. Once done, press the Back Arrow at the top left to return.

Update WebView

To update WebView, you need to find what WebView implementation is used on your device. In general, default implementation depends on the Android version as follows:

• Android 10.0 and higher - Android System WebView (opens new window).
• Android from 7.0 to 9.0 - Google Chrome (opens new window).
• Android 6.0.1 and lower - Android System WebView (opens new window).

Users of Android 7.0 and higher can also see and change WebView implementation in Developer Options (opens new window).

Non-standard implementations like Firefox can lead to Tachiyomi not working correctly or in the worst-case crash. We recommend to set WebView implementation to Android System WebView (opens new window) or Google Chrome (opens new window).