> ## Documentation Index
> Fetch the complete documentation index at: https://docs.stru.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Install & Sign In

> Set up the Stru AI Desktop Client on your Windows machine and pair it with your Stru AI account

## What the Desktop App Is

The **Stru AI Desktop Client** connects your Stru AI account to the engineering software already installed on your machine. With the desktop app running, the ETABS and SAP2000 agents build and analyze models directly in your own licensed copies of the software, on your hardware, with your files.

<CardGroup cols={2}>
  <Card title="Works with your licenses" icon="key">
    Drives the SAP2000, ETABS, and Mathcad installations you already own. Nothing extra to license.
  </Card>

  <Card title="Paired with your account" icon="link">
    One sign-in connects the desktop app to the same conversations, files, and agents as [app.stru.ai](https://app.stru.ai)
  </Card>
</CardGroup>

## Requirements

* **Windows** with SAP2000 and/or ETABS installed in their default locations (`C:\Program Files\Computers and Structures\...`)
* A **Stru AI account**
* An **internet connection**: the app connects to Stru AI each time it starts

<Info>
  macOS support is on the way. Today, agent-driven SAP2000/ETABS work runs on Windows.
</Info>

## Install

<Steps>
  <Step title="Download the installer">
    Download the latest **Stru AI Desktop Client Setup** (`.exe`) from the releases page.
  </Step>

  <Step title="Run the installer">
    Run the downloaded file and follow the prompts. The app launches when installation completes.
  </Step>

  <Step title="Let it set up your environment">
    On first launch, the app prepares its working environment automatically. You'll see a **"Setting up your environment"** progress screen. This one-time step typically takes about a minute.

    <Tip>
      If setup can't finish (for example, the connection dropped), restart the app. It picks up and retries automatically.
    </Tip>
  </Step>
</Steps>

## Sign In

<Steps>
  <Step title="Click Log In with Stru AI">
    The app opens your default browser to authorize the sign-in.
  </Step>

  <Step title="Authorize in the browser">
    If you're already signed in at [app.stru.ai](https://app.stru.ai), authorization is instant. Otherwise, sign in as usual. The browser shows a confirmation page when the desktop app is authorized.
  </Step>

  <Step title="Return to the app">
    The desktop app picks up the sign-in automatically, with no codes to copy. You land directly in the chat workspace.
  </Step>
</Steps>

<Accordion title="The app says the authorization timed out">
  The sign-in window stays open for 5 minutes. If it lapses, or the browser never returned to the confirmation page, click **Try Again** in the app and complete the browser step again.
</Accordion>

<Accordion title="Signing out (and unexpected sign-outs)">
  Sign out from **Settings → General → Account → Logout**. If the app returns you to the sign-in screen on its own (for example, after an extended time away), sign in again. Your conversations and settings are safe.
</Accordion>

## Staying Up to Date

Updates download automatically in the background. When one is ready, an **Update** button appears in the header. Click it and the app restarts on the new version in a few seconds. You can also check your current version anytime under **Settings → Software → Check for updates**.

<Warning>
  If SAP2000 or ETABS is running under Stru's control when you update or quit, the app asks for confirmation first, because updating closes that session. Save your model in SAP2000/ETABS before continuing. If you don't respond, the app proceeds automatically after about 10 seconds.
</Warning>

## Next Steps

<CardGroup cols={2}>
  <Card title="Connect ETABS & SAP2000" icon="plug" href="/desktop-app/connect-etabs-sap2000">
    Start your first agent-driven modeling session.
  </Card>

  <Card title="Settings & Troubleshooting" icon="sliders" href="/desktop-app/settings-and-troubleshooting">
    Tune the app and fix common hiccups.
  </Card>
</CardGroup>

<Info>
  **Questions?** Email **[support@stru.ai](mailto:support@stru.ai)** or [book a call](https://cal.com/bhosh).
</Info>