Cursor IDE Agent on Windows stuck on "Taking longer than expected…": `Timed out waiting for the agent host bridge to register.`

Context

Source(s): https://forum.cursor.com/t/cursor-ide-agent-not-working-agent-host-bridge-timeout/171920 Signal: 274 views; staff accepted answer; two users with different causes both reported it resolved (September 2026). Status: reported working by source, not reproduced by us.

Problem

On Windows, the Agent inside the Cursor IDE window stays on "Taking longer than expected…" for about a minute and then fails with the error above, even in an empty folder with a "Hello" message. The separate Agents window on the same PC works normally.

Error (redacted / normalized)

Timed out waiting for the agent host bridge to register.

AgentTurnClassifiedError: Timed out waiting for the agent host bridge to register; please retry.

Applies when

Windows 11 x64, Cursor 3.20.21 (user setup).

Confirm it is this problem

1. Send "hello" to the Agent in the IDE window of an empty folder. → expect: it times out with the agent host bridge error, while the Agents window answers.
2. Open View > Output and pick "Cursor Agent Host". → expect: errors from the local agent component (staff asked for this log).

Not this when / boundary

The Agents window also fails, or Network Diagnostics fail; that points to a network or account problem instead (our inference).

Root cause

Staff said the requests never leave the machine: a local component that runs agents inside the IDE window fails to come up, so the IDE gives up after about a minute. For the original poster staff changed something on their side; for a second user staff said a native component did not install correctly, and that user found the Microsoft Visual C++ runtime was missing.

Fix

1. Close Cursor, end every remaining Cursor process in Task Manager, reopen Cursor and send "hello" again (staff, after a change on their side). → expect: the original poster said it "was resolved the next day".
2. If it still fails and the logs show the native component failing (the second user's logs also showed "operation not permitted"), install or repair the Microsoft Visual C++ runtime, then fully restart Cursor. → expect: the second user said "The problem was finally resolved" after repairing the runtime libraries.
3. Staff's other suggestion if Cursor sits on a non-default or managed drive: reinstall the latest build from the official download page to the default location (settings and extensions are kept), or have IT allow Cursor to run its native files and write to its own folders there (not confirmed by a user; the second user fixed it with step 2 instead).

How to verify

The Agent in the IDE window answers "hello" within a few seconds, and the Cursor Agent Host output shows no startup errors.

What did not work

none reported in the thread.

Risks

The second user repaired the runtime with a third-party tool ("DX Repair"). Prefer Microsoft's official Visual C++ Redistributable installer over third-party repair tools (our inference). If you attach a debugging-data zip or logs to a public thread, check them for file paths and user names first (our inference).

Verified scope

Cursor 3.20.x on Windows, September 2026.

Becomes obsolete when

Cursor's installer ships or checks for the runtime it needs, and the server-side change is fully rolled out.