Claude Opus 4.6 Web: Troubleshooting and Fix Steps for “Unable to Send Messages”

When you encounter issues on the Claude Opus 4.6 web client such as “can’t send,” “keeps spinning,” or “no reply after sending,” in most cases it’s caused by the network, browser cache, or login state. Below is a Claude Opus 4.6 troubleshooting checklist from fastest to slowest, aiming to pinpoint the cause with minimal setting changes. After each step, go back to the chat page and try sending a short message to verify.

First, rule out server-side issues and network blocking (fastest way to locate)

First open Claude Opus 4.6’s status page (status.anthropic.com) to see whether there is any API instability; if there is an alert, waiting for recovery is more effective than repeatedly refreshing. If the status is normal but Claude Opus 4.6 still fails to send, test with a different network: switch from a company/campus network to a mobile hotspot—many “Network error/connection failed” cases come from gateway or proxy blocking. It’s also recommended to temporarily disable the system proxy, traffic-splitting tools, or the browser’s built-in “Secure DNS/acceleration,” to avoid routing Claude Opus 4.6 requests to unreachable paths.

Browser-related freezing: cache, extensions, cross-site restrictions

If the Claude Opus 4.6 chat page opens but you can’t send messages, first log in once using an incognito/private window; if it works in incognito, it’s basically a cache or extension conflict. Handle in order: first disable ad blockers/script-type extensions (uBlock, script managers, privacy-protection extensions are common), then clear this site’s cookies and cache and log back into Claude Opus 4.6. If you have enabled strict “block third-party cookies” or a site-isolation policy, it may also cause session tokens to fail to refresh; temporarily relax it and then try sending in Claude Opus 4.6 again.

Account and session anomalies: login invalidation, rate limits, and permissions

If Claude Opus 4.6 shows “fails immediately after sending/requires re-verification,” a common cause is an expired login state: log out and log back in—don’t just refresh the page. If you see something like “Too many requests/429,” it means too many requests in a short time; stop retrying continuously, wait a while, then send a shorter message, and reduce the number of Claude Opus 4.6 tabs open at the same time. Another often-overlooked factor is account verification: make sure email/phone verification is complete and the browser time is correct (time drift affects tokens), otherwise Claude Opus 4.6 may keep disconnecting.

Still not resolved: use “minimal reproduction” to improve the success rate of feedback

If Claude Opus 4.6 only can’t send in a specific conversation, first create a new blank conversation and send a test sentence to determine whether it’s “conversation corruption” or “site-wide unavailability.” Then record the error text at failure, the steps to reproduce, the browser version, and the network environment, and keep screenshots of any on-page prompts; these help support staff locate the Claude Opus 4.6 issue much more than “can’t send.” Only as a last step is it recommended to switch browser engines (swap between Chrome/Edge) or log in on a different device to confirm whether the issue is tied to the local environment.