Troubleshooting

Login Issues

“Invalid credentials” — Check username/password and Caps Lock.

“Device limit reached” — Revoke an old device from the Account section. A 12-hour cooldown applies before a new device can register.

“License expired” — Renew at krantz.run. No grace period — access stops immediately.

Checking Issues

High “Connection Failed” rate — Check internet, verify proxies work, reduce thread count, try without proxies.

Many “Rate Limited” results — Reduce threads, use more proxies, switch to residential proxies.

“Server Not Found” — Domain doesn’t exist or has no mail server configured.

Slow speed — Increase threads (Air: up to 500, Pro: up to 2000), use faster proxies.

Proxy Issues

“Proxy Error” on all checks — Verify format, test proxies manually, check auth credentials, try another provider.

Rate limited despite proxies — IPs may be flagged. Use residential proxies, add more proxies, lower thread count.

Application Issues

App won’t start:

  • Windows: Install Visual C++ Redistributable
  • Linux: Install WebKit2GTK: sudo apt install libwebkit2gtk-4.1-0
  • Antivirus: Add an exception for the krantz binary
  • Reinstall: krantz update mail or krantz update sorter

Crashes — Reduce thread count, check available memory, update with krantz update.

Getting Help

Contact support with your app version (krantz --version), OS, steps to reproduce, and error messages.

Reach us at krantz.run.