Install Jan on Windows

Goal

Jan installed, its engine ready, and its data folder at X:\Jan, where X: is the drive you picked in chapter 02 (D:, E:, F: or any drive that is not C:). On a Mac, go to chapter 04 instead.

Keep the internet on for this whole chapter.

1. Download

1. Open jan.ai and click Download for Windows.
2. Pick x64 for normal Intel and AMD laptops. Pick ARM64 only for Snapdragon laptops.
3. The file is called something like Jan_0.8.8_x64-setup.exe.

Only download from jan.ai or Jan's GitHub releases. Not from "free download" sites.

2. Install

1. Double-click the .exe.
2. If Windows shows "Windows protected your PC", check the file came from jan.ai, then click More info → Run anyway.
3. Wait. Jan opens by itself when it is done.

The app itself installs into your user folder on C:. The installer does not ask where. That is a few hundred MB at most. Your chats and models are the big part, and we move those in step 4.

3. First-time setup

Jan shows "Jan needs to set up on your system". Click Let's start.

1. Help improve Jan. This asks whether to share anonymous usage statistics (not your chats). Analytics are off by default. Click Deny to keep them off.
2. Setting up the local engine. Jan downloads the engine that runs models, plus a small model for file search. This needs internet and takes a few minutes.
3. A badge shows "Will use your GPU" or "Will run on CPU". Both are fine.
4. Wait for "Engine ready".
5. If it offers to download a first model, do not download yet. Move the data folder first.

4. Move the data folder off C:

By default Jan keeps everything in C:\Users\<you>\AppData\Roaming\Jan\data. Move it now, while it is still small.

1. Create the folder first: open File Explorer, go to your data drive (X:), and make a new folder called Jan.
2. In Jan, open Settings → General. Find App Data ("Location for messages, downloaded models and other data").
3. Click Change Location and choose X:\Jan.
4. Confirm. Jan stops, copies the current data into X:\Jan, and restarts.
5. Jan may show its setup screen again after the restart. That is normal. Go through it once more, and click Deny again on "Help improve Jan".

Rules Jan enforces:

• Not a drive root. X:\ is refused. Use a folder like X:\Jan.
• Not a Windows or Program Files folder, and not your user folder itself.

5. Clean up the old copy (optional)

Jan copies, it does not move, so the old data is still on C:. Once everything under "Check it works" below is true:

1. Close Jan fully (also from the system tray, the ^ near the clock).
2. Open %APPDATA%\Jan in File Explorer.
3. Delete only the data folder inside it.

Do not delete the whole Jan folder. The file settings.json next to data is what tells Jan to look in X:\Jan. Delete it and Jan goes back to C:.

Check it works

• Settings → General → App Data shows X:\Jan.
• X:\Jan in File Explorer contains folders such as threads, extensions and logs.

Exercise

Click Open Containing Folder next to App Data in Jan's settings. Which folder opens? It should be X:\Jan. Every chat you have from now on is saved in its threads folder.

If something goes wrong

• "Cannot relocate data folder to root directory": you picked X:\. Pick X:\Jan.
• Relocation fails: fully quit Jan, open %APPDATA%\Jan\settings.json in Notepad, and set "data_folder": "X:\\Jan" (two backslashes). Save and reopen Jan. This is from Jan's troubleshooting guide.
• Setup stuck on the engine download: check your internet, then click Re-run checks.

Sources: Install on Windows, Data folder, Jan v0.8.8 source (relocation code).