Claude is very good and occasionally very confusing. A paste arrives empty. An upload fails and blames your internet, which is fine. A response stops halfway through a sentence.
Most of these have a specific cause and a specific fix, and most of the advice online is either generic or out of date. These pages are the ones we keep for ourselves, written up properly, and corrected when Anthropic changes something.
The guides
Claude says your pasted text is empty? Five fixes
A long paste stops being a message and becomes an attachment called pasted text.txt. How to tell which happened, and what to do when it arrives empty.
Claude file upload not working? Seven fixes
Claude accepts 500MB per file in a chat but only 30MB in a project, and that mismatch causes most upload failures. Every error, with the fix.
Claude stopped mid-sentence? Why, and how to get the rest
Replies stop mid sentence for a few specific reasons. How to tell which one you hit, and how to get the rest of the answer back.
Claude network error or "something went wrong"? Fixes for each one
Upload failed due to a network issue is rarely your connection. The real causes, in the order worth checking them.
"Authentication service was unavailable. You can try again." What the Claude error means
Getting "Authentication service was unavailable" in Claude? What the error means, why logging back in does not fix it, and how to check.
Claude artifacts not working? Start with the setting everyone misses
Artifacts that will not render, will not update, or vanish from the sidebar. What causes each one, and how to get the panel back.
Claude chats disappeared? Where to look before assuming they are gone
Conversations vanish from the sidebar for a handful of specific reasons, and most of them are recoverable. How to check each one, in order.
Why we write these
We build lead attribution software, which is a long way from browser caches and upload endpoints. But we use Claude every day, we hit these faults ourselves, and the pages we found while looking for answers were mostly wrong. So we wrote better ones.
If a fix on any of these pages has stopped working, or Anthropic has changed something and we have not caught up, tell us and we will update it.
Most of these fixes are about the chat app. If you use Claude Code to build software rather than to chat, the practices that keep an unattended, multi-day build safe are a different set of tools entirely: the control surface behind an autonomous build.
Written by the team at Lead Source, where the day job is working out which marketing actually brings customers.