Cowork: App Freezes or Stops Responding — Fix

A Cowork window stops accepting input, leaves a spinner running, or appears frozen for a minute or longer. The chat usually still works underneath; it's the UI thread that has stalled. Most freezes resolve in 30 seconds with a reload or a click of the stop button. If it's recurring, check your disk space and RAM.

Quick Fix

1. Wait two minutes. Long agent runs (research that fetches dozens of pages, file operations across hundreds of files) genuinely take time. If a real run is happening, the UI will resume on its own.
2. If the spinner is still running and the UI is still unresponsive, click the stop button (square icon) next to the input box. This cancels the in-flight tool calls and returns the app to idle.
3. If the app is still frozen after clicking stop, reload the window: Cmd+R on macOS or Ctrl+R on Windows. The chat history is preserved, the UI rebuilds, and any orphaned tool calls are dropped.

If the app responds after one of these steps, you're done. If freezes happen repeatedly on the same kind of request, continue to the next section.

Frozen UI Thread (Most Common)

How ScaleIT handles this: See AI Quick-Start

Cowork runs in two parts: the chat engine (which usually keeps working) and the UI thread (which displays the chat and accepts input). On complex requests or during heavy connector calls, the UI thread can stall even though the underlying work continues. A reload or stop fixes it immediately.

Fix: Follow the Quick Fix steps above. Most freezes clear with a reload or stop button. The underlying work completes cleanly once the UI comes back.

Orphaned Tool Calls

Rarely, a previous tool call doesn't finish cleanly and blocks the UI from accepting new input. The chat engine is waiting for a result that will never come. A full app restart drops the orphaned call and frees the UI.

Fix:

1. Quit Cowork entirely. On macOS, Cmd+Q; on Windows, Alt+F4 or close the window.
2. Wait 10 seconds.
3. Relaunch Cowork.
4. The chat history is preserved, the connector auths are preserved, but orphaned tool calls are dropped. The app should respond normally.

If the freeze returns on the exact same prompt, save that prompt and report it.

Insufficient Disk Space or RAM

Cowork keeps session state and tool outputs on local disk. A drive that is over 95% full or a machine with almost no free RAM will produce UI hangs that look like a Cowork bug.

Fix:

• macOS: Open Activity Monitor (Cmd+Space, search "Activity Monitor"). Check the Memory tab. If "Memory Pressure" is red or orange, close other apps to free RAM.
• Windows: Open Task Manager (Ctrl+Shift+Esc). Check the Performance tab. If memory is above 90%, close other apps.
• Disk space: Open Finder (macOS) or File Explorer (Windows) and check your drive's free space. If less than 10% remains, delete large files or temporary data. Cowork will resume normal operation once space is freed.

Verify

• The Cowork window accepts input normally (you can type in the chat box).
• A new prompt executes without stalling or freezing.
• The UI responds within 2 to 3 seconds of a click or keystroke.

Still Failing?

If freezes happen repeatedly even after reloading and checking disk/RAM:

1. Note the exact prompt or action that triggers the freeze.
2. Try the same prompt on a fresh Cowork instance (quit and relaunch).
3. If the freeze repeats on the same prompt consistently, save the prompt word-for-word.
4. Contact ScaleIt with the exact prompt and the steps you've taken. Reproducible freezes are the easiest class for the vendor to fix, and we can help escalate to Anthropic if needed.

Losing productivity to app freezes instead of building workflows? ScaleIt can help configure your Cowork instance for stability. Contact us for a free consultation.