Error messages

Connection failed. Please try again, or contact support if the issue persists

Connection failed. Please try again, or contact support if the issue persists

Cursor shows this in the chat when a request to the model fails partway or never gets going:

Connection failed. Please try again, or contact support if the issue persists

Older builds said "Connection failed. If the problem persists, please check your internet connection or VPN." That version is still pasted all over the forum, and the VPN hint in it sends a lot of people down the wrong path. As of September 25, 2026 the Cursor forum has 244 topics with "connection failed" in the title.

First, is it the network at all?

Cursor has a built-in check for this. Open Settings > Network and press Run Diagnostics. In the replies we read, Cursor staff use its result to split the problem in two. If the Chat and Agent checks come back green, your connection to Cursor is fine and the fault is local, usually in the chat. If they fail, it's the network path.

We were surprised how often it's the first case. In three of the four staff replies we read, the network was fine.

If the chat is the problem

Start a new chat and send the same prompt. Staff have given two reasons an old chat keeps failing:

• It got too long. In June, a user on Cursor 3.7.42 saw every request fail with [unavailable] PING timed out in the logs. Cursor's reply was that the chat had grown past the model's context limit, and the automatic summarizing (Cursor shrinking old turns to make room) couldn't bring it back down.
• It lost its folder. On Cursor 3.8.11 the log showed No resource accessor found for composer. Staff said that happens when the agent can't tie the chat to an open project folder, so open one with File > Open Folder, then start a new chat.

The old chat won't recover, but its text is still there. Copy out what you need first.

If it's your network

When a request doesn't reach Cursor at all, staff point at VPNs, proxies and corporate firewalls (a July reply named Zscaler) that inspect encrypted traffic. The fix they give most is to drop to HTTP/1.1:

"cursor.general.disableHttp2": true

Add that to your settings, or use Settings > Network > HTTP Compatibility Mode, then restart Cursor. If that doesn't do it, turn the VPN or proxy off for a minute, or try a phone hotspot to see if your network is the difference.

Diagnostics green and still failing

There's a newer cause in September 2026. A user got this message with Timed out waiting for the agent host bridge to register; please retry. in the details. A Cursor staffer said on September 24 that it "happens locally, before the request even leaves Cursor", because a background part of the agent didn't start after an update. That's why diagnostics stayed green. Their fix is a clean reinstall: quit Cursor, end any leftover Cursor processes, then install the latest build from Cursor's download page. They called it a known issue they're tracking.

If nothing here helps, the forum team asks for the Request ID (chat menu, top right, Copy Request ID) and your diagnostics output. status.cursor.com shows whether there's an outage.