> For the complete documentation index, see [llms.txt](https://spectra-2.gitbook.io/spectra-ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://spectra-2.gitbook.io/spectra-ai/setup/environment-setup-and-software-installation.md).

# Environment Setup & Software Installation

To run SpectraAI correctly, strict adherence to the environment setup is required. Please follow the steps in the exact order presented in this part of the guide: [Remove Previous Python Versions](/spectra-ai/setup/environment-setup-and-software-installation/remove-previous-python-versions.md) .

## Installing Python 3.11.9

Installing Python is straightforward, but for the best experience on Windows, you must select two specific configuration options to avoid common errors. 

***

### 1. Download the Installer

1. Visit the [Python 3.11.9 Release Page](https://www.python.org/downloads/release/python-3119/).
2. Scroll down to the **Files** table at the bottom.
3. Download the **Windows installer (64-bit)**.

<figure><img src="/files/dwByLBP9lH7CVJmjyBPS" alt=""><figcaption></figcaption></figure>

***

### 2. Configuration During Installation

When you run the installer, follow these steps carefully:

#### A. Add Python to PATH

On the very first screen, look at the bottom:

* **Check the box:** `Add python.exe to PATH`.
* **Click:** `Install Now`.

> **Note:** If you miss this step, you will not be able to run Python from the Command Prompt without manually editing your system environment variables. In case you didn't uninstall and run installation again

<div align="left"><figure><img src="/files/CKybWgB26akt2tYMfHrD" alt="" width="327"><figcaption></figcaption></figure></div>

#### B. Disable Path Length Limit

Once the installation finishes, the "Setup was successful" screen will appear.

* Look for the option: **"Disable path length limit"**.
* **Click it** (you may need to grant Administrative permission).

> **Why?** This removes the 260-character limitation for file paths, which is essential for complex Python projects and library management.

<div align="left"><figure><img src="/files/9G8yAKO2jvmMXfMHE13h" alt=""><figcaption></figcaption></figure></div>

***

### 3. Verify the Install

To confirm Python is ready to use:

1. Press the Win button on your keyboard and type **Command Prompt,** or **PowerShell**.
2. Type the following command and press Enter:

```bash
python --version
```