Diagnosis
A structured technical workflow for isolating whether an issue is caused by your device environment, local network, application configuration, or an upstream source outage.
1. Network vs Source Isolation
Before submitting a bug report or clearing application data, determine if the failure originates from your connection or the target website:
Test in a standard browser: Open Chrome or Firefox on your device and navigate to the source website directly.
- If the site fails to open, times out, or returns a 502/503 Cloudflare gateway error, the source itself is undergoing downtime or maintenance.
- If the site opens cleanly in your browser but fails inside Wammy, an anti-bot check or outdated User Agent is likely intercepting API calls.
Test across alternate networks: Switch from Wi-Fi to mobile cellular data (or vice versa). If the error disappears, your Wi-Fi router DNS or ISP is filtering the domain.
2. Common Exception Codes
When inspecting error toasts or crash dump files, look for these standard exceptions:
SSLHandshakeException / CertPathValidatorException
- Cause: Your device cannot verify the remote server's SSL/TLS certificate.
- Occurrence: Common on older Android versions (Android 7 and below) missing modern Let's Encrypt ISRG Root X1 certificates.
- Remedy: Update your system security components, or verify that your device date and time are accurately set to network synchronization.
SocketTimeoutException
- Cause: The remote server failed to respond within the configured timeout window (usually 30 seconds).
- Remedy: The source is experiencing heavy load. Retry in a few minutes or throttle background downloads.
JsonSyntaxException / NullPointerException during search
- Cause: The source website changed its HTML layout or JSON API schema.
- Remedy: Aggregator websites update their CSS classes and frontend endpoints regularly. Check the Changelogs or update to the latest Wammy release to obtain updated scrapers.
3. Isolating Storage & Permissions
If downloads fail instantly with an IO error:
- Verify available device storage: Wammy requires at least 500 MB of free internal space for image caching and zip archive generation.
- Check directory write permissions under Settings > Data and storage > Storage location.
- If using an external microSD card, confirm the card has not mounted as read-only due to hardware filesystem errors.
4. Resetting Application Caches Safely
When an unexpected state persists across reboots, reset internal caches in order without losing your library or reading history:
- Clear Image Cache: Navigate to More > Settings > Advanced > Clear image cache. This removes cached thumbnail bitmaps without deleting reading progress.
- Clear Chapter Cache: Navigate to More > Settings > Advanced > Clear chapter cache. This purges temporary reader buffer files.
- Clear Cookies & WebView Data: Navigate to More > Settings > Advanced > Clear cookies and Clear WebView data.
- Backup before full reset: If a full reinstallation is necessary, always create a fresh backup file via More > Settings > Data and storage > Create backup or verify your Google Drive cloud sync status first.