Common Causes and Fixes for Login Failures
Login failures are among the most frustrating issues when using Claude. Typical symptoms include the page not responding after entering credentials, an "Invalid credentials" message, or the app crashing immediately. These errors are often related to network conditions or cached data.
First, clear your browser cache and cookies, then try logging in again using incognito mode. If the problem persists, check whether your account has been temporarily locked—multiple incorrect password attempts trigger a security mechanism. Wait 15–30 minutes and try again. Additionally, network nodes in some regions may be restricted; switching to a reliable proxy tool often resolves the issue quickly.
Typical API Error Scenarios and Their Fixes
Developers and advanced users calling the Claude API may encounter common errors such as "429 Too Many Requests", "401 Unauthorized", and "500 Internal Server Error". Each has a different underlying cause.
A 429 error means you've hit the rate limit—reduce request frequency or upgrade your API plan quota. A 401 error usually indicates an expired, compromised, or insufficiently scoped API key—regenerate and update the key immediately from your dashboard. A 500 error is a temporary server-side issue; retry after a few minutes, or check the Anthropic status page to confirm if there's a widespread outage.
Conversation Interruptions and Failed Message Sends
Sometimes while using Claude, you may experience long delays after sending a message or a sudden disconnection. This often relates to network stability or browser compatibility.
First, try refreshing the page or restarting the app. If messages still won't send, check whether your WebSocket connection is being blocked by a firewall. Older browsers (such as Internet Explorer or older Safari versions) may not fully support Claude's dynamic interactions—upgrade to the latest Chrome or Edge. Also, if your conversation contains an extremely long context (over 100K tokens), it could cause memory overflow and freeze the interface. In that case, start a new conversation and break your questions into smaller parts.
What to Do If Your Account Is Flagged or Banned
A small number of users report seeing a "Suspicious activity detected" notice or even a full account ban. This usually happens due to triggering anti-abuse mechanisms, such as registering many accounts in a short period, using non-compliant virtual phone numbers, or operating too many accounts from the same IP address.
If your account was mistakenly banned, submit an appeal through the official customer support channel immediately. Include your registered email address and a screenshot of the last time you used the account normally. When writing the appeal, avoid machine translation; describe your usage scenario in natural language to increase the chances of approval. Also, check whether any insecure third-party services are linked to your account and revoke those authorizations to reduce risk.
