Claude FAQ: Can't log in, upload failures, and conversation saving

When using Claude, what most often gets people stuck isn’t the question itself, but login verification, file uploads, or conversation history not syncing. Below, these high-frequency issues are broken down and explained clearly, with a troubleshooting order you can apply immediately. You can follow along section by section; usually you can get Claude working normally again within a few minutes.

Claude login failure: CAPTCHA keeps spinning or keeps returning to the homepage

If the Claude login page keeps refreshing and the verification button keeps spinning, a common cause is browser cache or script blocking. First clear the Cookies and cache for the Claude site, then retry in an incognito/private window—this has a high success rate.

If it still doesn’t work, check whether browser extensions (ad blockers, privacy protection, script managers) are affecting Claude’s verification flow; it’s recommended to temporarily disable them and then log in again. An unstable network can also cause it to jump back to the homepage—switching to a more stable connection can save time.

Claude file upload failure: stuck uploading or says unsupported

If Claude upload fails, first confirm whether the file format is supported and whether the file size is too large. Compress scanned PDFs first, or convert images to more common formats—this usually resolves it. If a document contains many ultra-high-resolution images, consider splitting it into multiple smaller files and have Claude handle them separately.

Also, filenames with special symbols may trigger upload errors; rename the file using an English/number combination and try again. If Claude reports a parsing failure, you can continue by using “copy key passages + paste in batches.”

Claude replies get cut off: what to do if it stops halfway

If Claude stops midway through a long answer, it’s mostly because the output length or context is nearing the limit, and not necessarily a system failure. The most direct approach is to reply “continue” in the same conversation, adding “start from where you left off.”

If you want Claude to produce a more complete result in one go, split the task into “outline first — write by chapters — then polish uniformly at the end.” If you frequently have Claude process very long source texts, you can also ask it to extract key points first and then do deeper work on those points; stability will be better.

Claude conversation history not syncing: can’t find past chats or new chats aren’t saved

If Claude history occasionally doesn’t display, don’t assume it’s lost right away: refresh the page, log out and back in, or cross-check by using another login method for the same account. In many cases it’s just that the page cache hasn’t updated; after reloading, the Claude conversations will return.

If you switch between multiple devices, make sure you’re using the same Claude account (same email / same third-party login entry) to avoid situations where it “looks like the same account but actually isn’t.” For important content, it’s recommended to periodically copy it into local notes to reduce misjudgments caused by sync delays.