If Claude won’t open, messages won’t send, or file uploads fail, it’s usually not because your “account is broken,” but because of abnormal browser cache, network routing, or permission/session state. Below is a prioritized Claude troubleshooting checklist, starting with the quickest fixes. Each step can be verified independently to avoid wasting time on repeated retries.
Start with a 3-minute basic Claude troubleshooting: login state, cache, and extensions
First, confirm whether you’ve been switching between multiple accounts in the same browser; this can easily cause session state confusion, so it’s recommended to log out and then log back in once. Next, open Claude in an incognito/private window—if it works there, it’s likely a cache or cookie issue; clear the site data and try again. Finally, temporarily disable ad blockers, privacy protection, and script-management extensions, as these often block uploads and requests.
Claude file/image upload failure: format, size, and network interruptions
When troubleshooting Claude for “upload failed / stuck uploading,” first check whether the file is too large or in an uncommon format; try converting it to PDF, PNG/JPG, or plain text and retry. An unstable network can cause the upload progress to roll back, so switch to a more stable connection, or compare by using wired internet vs. a mobile hotspot. If it keeps spinning with no result, refreshing the page will lose the upload queue—copy your problem description locally first, then reselect the file and submit again.
Message send timeout or “Network Error”: prioritize proxy and DNS
For this type of Claude troubleshooting, focus on “connection quality.” On the same network, first compare whether a phone’s mobile-data hotspot works normally to rule out local router/broadband issues. If you’re using a proxy tool, try switching nodes or comparing global vs. rule-based modes; some nodes make long connections unstable and cause timeouts. You can also change DNS to a commonly used public DNS and restart the browser to avoid resolving to problematic routes.
Model unavailable / usage prompts: queuing, quotas, and workspace permissions
If you see “model unavailable,” refresh and wait a bit before trying again—this commonly happens during temporary server-side congestion; repeated retries in a short time can instead trigger risk controls. If you see usage-related prompts, reduce the length of a single input, split tasks, and disable unnecessary attachments and long text quotes. If you’re using Claude in a workspace and troubleshooting still doesn’t help, check whether you accidentally switched to a workspace/organization you don’t have permission for; switch back to your personal space and verify again.
Still not resolved: record details and submit feedback to avoid guesswork
If issues persist after the above Claude troubleshooting, record three things: the exact error message, the steps to reproduce, and your browser/network environment (proxy or extensions). Then submit via the help/feedback entry on the page, including screenshots and the reproduction path—this will significantly improve handling efficiency. As a temporary workaround, you can switch browsers or log in on another device to get the task done first, then gradually pinpoint the root cause.
