Claude Troubleshooting: Fixing Send Failures, Interrupted Responses, and Attachment Upload Issues

The most annoying things about using Claude are “can’t send,” “stops halfway through a reply,” and “can’t upload attachments.” This article lays out a Claude troubleshooting workflow in the order you’d actually use it: check the server first, then your network and browser, and finally your account and file issues. Follow it and you can usually pinpoint the cause in just a few minutes.

Start with basic troubleshooting: confirm whether it’s a server-side fluctuation

Before you begin troubleshooting, first check whether Claude is unstable overall: open Anthropic’s status page or quickly try again on a different network. If multiple devices at the same time are seeing send failures or endless loading spinners, it’s more likely server congestion—repeatedly refreshing will only make it easier to trigger rate limits.

The conclusion at this step is simple: if the status page shows an incident, wait a bit and try again; if the status is normal, proceed to the local troubleshooting steps below.

Troubleshooting send failures: network, browser, and extensions are the most common

When Claude fails to send, troubleshoot the network first: switch between Wi‑Fi and cellular, disable your proxy or change nodes, and make sure login and requests go through the same network environment. Then troubleshoot the browser: sign in again in an incognito window and clear cache and cookies—many cases of “click send and nothing happens” are due to cache issues or an expired session.

If you have ad blockers, script managers, or privacy extensions installed, temporarily disable them and try again. After an extension blocks a request, the page may look normal, but the message will silently fail to send.

Troubleshooting interrupted/stuck replies: conversation length and input size

If Claude stops halfway through a response, shows an error, or even “regenerate” fails, treat it as a troubleshooting case of load or context pressure. First, break the task into smaller parts: reduce the amount of long text pasted in one go, and change “write it all at once” to output in sections—this often restores it immediately.

Very long conversations are also more likely to run into issues. When troubleshooting, copy the key information and start a new conversation to ask again. This effectively clears the context and reduces the chance of truncation or getting stuck.

Troubleshooting attachment upload issues: format, size, and permissions

If an attachment fails to upload, start troubleshooting with the file itself: confirm the format is a common type Claude supports, keep the file from being too large, and avoid special characters in the filename; then resave the file and upload again to rule out corruption or encoding issues.

If a work computer or managed browser restricts local file permissions, that can also cause “selected it but it won’t upload.” For this kind of troubleshooting, test on a personal device or a different browser; also confirm your current account has access to attachments—otherwise it may look like a malfunction when it’s actually a permission issue.