If Claude suddenly shows a blank screen, throws a 403, or won’t send messages, it’s usually not because “you did something wrong,” but because something in the chain broke. Follow the troubleshooting flow below in order, and you can locate most issues to the network, browser, account permissions, or server status. Each step aims to narrow down the problem with the fewest actions possible.
First, do the “easiest” troubleshooting split for Claude errors
The first step in Claude troubleshooting is to confirm whether the problem is on your side or the platform’s: switch to a different network (toggle between Wi‑Fi and hotspot) and try again. Then log in using an incognito/private window to avoid interference from old cache and extensions. If it works normally in incognito but fails in a regular window, you can basically pin it down as a browser-environment issue—this is the most common troubleshooting conclusion.
403 / permission anomalies: prioritize checking login method and regional network
If you encounter a 403 or “no permission to access,” Claude troubleshooting should first check whether you’re logged into the correct account: don’t mix email login with third-party login entry points; log out and log back in through the same entry point. Then check whether a corporate network, proxy rules, or security software is blocking the login callback; temporarily disable relevant blocking and try again. If switching networks immediately fixes it, it indicates a network policy is causing abnormal permission validation—subsequent troubleshooting should focus on the network.
Loading failures, stuck chats, missing history: “targeted cleanup” beats clearing all cache
For these issues, Claude troubleshooting does not recommend starting with “clear all cache.” First disable browser extensions (especially ad blockers, script managers, and privacy/anti-tracking tools), then refresh the page. If it’s still stuck, then clear only the site data (that site’s cookies and cache) to avoid logging out of other sites. If history occasionally doesn’t sync, first confirm whether you switched workspaces/accounts—many “session losses” are actually just looking at the wrong account, and this is the easiest thing to overlook in troubleshooting.
Attachment failures and truncated replies: troubleshoot starting from the file itself
If uploads fail, Claude troubleshooting should first do a “minimal test” on the file: try a smaller file, switch to a common format, remove special characters from the filename, and upload again. This quickly tells you whether it’s a file issue or a network issue. If replies are truncated or incomplete, it’s usually related to overly long or overly dense input; try splitting the task into two messages, and add at the end: “Please output in sections and indicate to continue at the end of each section.” If the same issue reproduces across different devices, it can basically be judged not to be a local issue, and troubleshooting should shift toward service status and account limits.
Still not resolved: collect key information before submitting feedback
If the above Claude troubleshooting steps are all ineffective, don’t waste time retrying repeatedly—directly record three things: a screenshot of the error message, the time it occurred, and the troubleshooting actions you’ve already taken (e.g., incognito / switching networks / disabling extensions). This information helps support staff reproduce the problem faster and avoids them asking you the same questions repeatedly. At this point, the goal of troubleshooting is to “describe the problem clearly,” not to keep blindly trying.
