# Excel Local AI Add-in — Install & Troubleshoot

## Prerequisites
- LM Studio running with local server on port 1234
- nginx reverse proxy from :1235 → :1234 with HTTPS + CORS

## Step 1: Trust the SSL certificate

```bash
# System-level trust (Excel's webview checks this)
sudo security add-trusted-cert -d -r trustRoot \
  -k /Library/Keychains/System.keychain \
  /opt/homebrew/etc/nginx/lm-studio.crt

# User-level trust (belt and suspenders)
security add-trusted-cert -d -r trustRoot \
  -k ~/Library/Keychains/login.keychain-db \
  /opt/homebrew/etc/nginx/lm-studio.crt
```

## Step 2: Configure nginx to serve these files

Add this to your nginx config (same server block that proxies :1235 → :1234):

```nginx
# In the server block for port 1235:

# Serve add-in files
location /taskpane.html {
    alias /Users/YOUR_USERNAME/excel-local-ai-addin/taskpane.html;
    add_header Access-Control-Allow-Origin "*";
}
location /functions.json {
    alias /Users/YOUR_USERNAME/excel-local-ai-addin/functions.json;
    add_header Access-Control-Allow-Origin "*";
}
location /manifest.xml {
    alias /Users/YOUR_USERNAME/excel-local-ai-addin/manifest.xml;
    add_header Access-Control-Allow-Origin "*";
}
# Icon placeholders (1x1 transparent PNG base64)
location /icon-16.png { return 200 "iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH5QEXBSsYkYMg5wAAABl0RVh0Q29tbWVudABDcmVhdGVkIHdpdGggR0lNUFeBDhcAAAAVSURBVDjLY2AYBaNgFIyCUTAKRsEoAgAHBAABKOTFyAAAAABJRU5ErkJggg=="; add_header Content-Type image/png; }
location /icon-32.png { return 200 "iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAYAAABzenr0AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH5QEXBSsYkYMg5wAAABl0RVh0Q29tbWVudABDcmVhdGVkIHdpdGggR0lNUFeBDhcAAAAVSURBVDjLY2AYBaNgFIyCUTAKRsEoAgAHBAABKOTFyAAAAABJRU5ErkJggg=="; add_header Content-Type image/png; }
location /icon-64.png { return 200 "iVBORw0KGgoAAAANSUhEUgAAAEAAAABACAYAAACqaXHeAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH5QEXBSsYkYMg5wAAABl0RVh0Q29tbWVudABDcmVhdGVkIHdpdGggR0lNUFeBDhcAAAAVSURBVDjLY2AYBaNgFIyCUTAKRsEoAgAHBAABKOTFyAAAAABJRU5ErkJggg=="; add_header Content-Type image/png; }
location /icon-128.png { return 200 "iVBORw0KGgoAAAANSUhEUgAAAIAAAACACAYAAADDPmHLAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH5QEXBSsYkYMg5wAAABl0RVh0Q29tbWVudABDcmVhdGVkIHdpdGggR0lNUFeBDhcAAAAVSURBVDjLY2AYBaNgFIyCUTAKRsEoAgAHBAABKOTFyAAAAABJRU5ErkJggg=="; add_header Content-Type image/png; }

# Existing proxy
location /v1/ {
    proxy_pass http://127.0.0.1:1234/v1/;
    proxy_set_header Host $host;
    add_header Access-Control-Allow-Origin "*" always;
    add_header Access-Control-Allow-Methods "GET, POST, OPTIONS" always;
    add_header Access-Control-Allow-Headers "Content-Type, Authorization" always;
    if ($request_method = OPTIONS) { return 204; }
}
```

Then reload:
```bash
sudo nginx -t && sudo nginx -s reload
```

## Step 3: Copy the add-in files

```bash
# Copy add-in files to your home folder (nginx will serve from here)
mkdir -p ~/excel-local-ai-addin
cp /tmp/excel-local-ai-addin/* ~/excel-local-ai-addin/
```

## Step 4: Sideload into Excel

```bash
# Create the wef folder if it doesn't exist
mkdir -p ~/Library/Containers/com.microsoft.Excel/Data/Documents/wef/

# Copy the manifest
cp ~/excel-local-ai-addin/manifest.xml \
   ~/Library/Containers/com.microsoft.Excel/Data/Documents/wef/local-ai-manifest.xml
```

## Step 5: Restart Excel and Test

1. **FULLY QUIT** Excel (Cmd+Q — don't just close the window!)
2. Wait 5 seconds
3. Reopen Excel
4. Go to **Home tab → Add-ins → Local AI** (should appear)
5. Click "AI Chat" in the ribbon
6. Type `=AI_LOCAL("What is a p-value?")` in any cell

---

## Troubleshooting

| Symptom | Fix |
|---|---|
| Add-in doesn't appear in Home → Add-ins | Restart nginx (`sudo nginx -s reload`), verify `https://127.0.0.1:1235/taskpane.html` loads in Safari |
| `#NAME?` error showing `_xldudf_AI_LOCAL` | Clear Office cache: Delete `~/Library/Containers/com.microsoft.Excel/Data/Library/Caches/`, FULL quit, reopen |
| `#VALUE!` or `#ERROR:` in cell | Check nginx is running, verify `curl -k https://127.0.0.1:1235/v1/models` works |
| "Network request failed" | Certificate not trusted at system level. Re-run Step 1. |
| Add-in loads but custom functions don't register | Make sure SharedRuntime is enabled. Check manifest has `<Set Name="SharedRuntime" MinVersion="1.1"/>` |
| Manifest XML fails to load | Validate: `xmllint --noout manifest.xml` |