When using Claude Opus 4.6, if you run into endless loading spinners, errors, or attachments that won’t open, most issues can be resolved through local self-checks. Below is a practical troubleshooting sequence organized by the most common scenarios: first eliminate the items that can restore functionality immediately, then decide whether to submit feedback.
Start with two quick troubleshooting steps: environment and account
Step 1 is to switch environments: open Claude Opus 4.6 in an incognito window, don’t install extensions yet, and don’t enable proxy routing, to rule out extension conflicts and cache contamination. Step 2 is to switch networks: swap between a mobile hotspot and home broadband; if the hotspot works, the issue is likely with local DNS or your company network policy.
Messages won’t send or it keeps loading: request blocking and rate limiting
If you see “Send failed / keeps loading,” first check whether your input is too long or whether you pasted a large amount of code or tables at once; it’s recommended to split it into multiple messages. Next, troubleshoot by refreshing the page and logging in again; if it still doesn’t work, clear the site’s cookies and cache and retry—many stuck session states are resolved at this step.
Replies get cut off or show blank: troubleshooting rendering and session-state issues
If Claude Opus 4.6 stops halfway through output or displays blank content, troubleshooting should prioritize copying the content already generated to avoid losing it after a refresh. Then troubleshoot by disabling extensions that may rewrite the page, such as “Reader Mode / script blockers / ad blockers,” and try a different browser engine (e.g., switch from Chromium to Safari/Firefox).
Attachment upload fails or can’t be parsed: troubleshooting format, size, and permissions
For attachment-related troubleshooting, first check three things: whether the file is encrypted, whether it has been repackaged by a cloud drive, and whether the filename contains special characters. Converting the file to a common format and exporting it again (reprint a PDF, Save As a PNG/JPG for images) usually works; if you’re on a corporate computer, also confirm whether the browser is blocked from reading local files or whether security software is blocking uploads.
Still getting errors: collect information first to submit feedback faster
If troubleshooting doesn’t work, it’s recommended to record the error message, the steps to reproduce, your browser version, and the results of network switching, and keep screenshots. Reproduce the same issue once in Claude Opus 4.6 with a shorter input—the smallest reproducible example is most helpful for diagnosis; if you see HTTP 429 or 5xx, you usually can only wait for the server to recover, while reducing frequent refreshes and repeated submissions.
