# Troubleshooting: App Not Starting

## 🐛 Problem: "Nothing happens when I run the app"

This usually means the application is hanging during startup, most likely during database migration or seeding.

---

## 🔍 Quick Diagnostics

### Step 1: Check What's in the Console

When you run `dotnet run`, you should see output. What do you see?

#### ✅ GOOD - You should see this:
```
Building...
info: Microsoft.Hosting.Lifetime[14]
      Now listening on: https://localhost:7001
info: Microsoft.Hosting.Lifetime[14]
      Now listening on: http://localhost:5001
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
```

#### ❌ BAD - If you see this (or nothing):
```
Building...
[Hangs here - nothing else appears]
```

This means it's **stuck during startup**, likely during database migration.

---

## 🛠️ Solution 1: Skip Automatic Migrations (Recommended)

The issue is that the app tries to migrate the database on startup. Let's disable that temporarily.

### Update Program.cs

**Comment out the automatic migration section:**

Find this section in `src/PowderCoating.Web/Program.cs` (around line 112-133):

```csharp
// Seed database with initial data
using (var scope = app.Services.CreateScope())
{
    var services = scope.ServiceProvider;
    try
    {
        var context = services.GetRequiredService<ApplicationDbContext>();
        var userManager = services.GetRequiredService<UserManager<ApplicationUser>>();
        var roleManager = services.GetRequiredService<RoleManager<IdentityRole>>();
        
        // Run migrations
        await context.Database.MigrateAsync();
        
        // Seed roles and admin user
        await SeedData.InitializeAsync(services, userManager, roleManager);
    }
    catch (Exception ex)
    {
        var logger = services.GetRequiredService<ILogger<Program>>();
        logger.LogError(ex, "An error occurred while migrating or seeding the database.");
    }
}
```

**Replace it with:**

```csharp
// NOTE: Database seeding is disabled for now
// Run migrations manually with: dotnet ef database update
// Seeding will happen on first database update

// Uncomment below after you've created the database manually:
/*
using (var scope = app.Services.CreateScope())
{
    var services = scope.ServiceProvider;
    try
    {
        var userManager = services.GetRequiredService<UserManager<ApplicationUser>>();
        var roleManager = services.GetRequiredService<RoleManager<IdentityRole>>();
        
        // Seed roles and admin user (no migration here)
        await SeedData.InitializeAsync(services, userManager, roleManager);
    }
    catch (Exception ex)
    {
        var logger = services.GetRequiredService<ILogger<Program>>();
        logger.LogError(ex, "An error occurred while seeding the database.");
    }
}
*/
```

### Then Manually Create the Database

```bash
cd src/PowderCoating.Web

# Create migration
dotnet ef migrations add InitialCreate --project ../PowderCoating.Infrastructure

# Apply migration
dotnet ef database update --project ../PowderCoating.Infrastructure
```

### Now Run the App Again

```bash
dotnet run
```

It should start immediately!

---

## 🛠️ Solution 2: Check SQL Server Connection

If the app is hanging, it might be trying to connect to SQL Server but failing.

### Is SQL Server Running?

**Windows - Check Service:**
```powershell
Get-Service MSSQL$SQLEXPRESS

# If not running:
Start-Service MSSQL$SQLEXPRESS
```

**Or use Services.msc:**
1. Press `Win + R`
2. Type `services.msc`
3. Find "SQL Server (SQLEXPRESS)"
4. Check if it's running

### Test Connection String

The app uses this connection string (in `appsettings.json`):
```json
"Server=.\\SQLEXPRESS;Database=PowderCoatingDb;Trusted_Connection=true;MultipleActiveResultSets=true;TrustServerCertificate=true"
```

**Test it manually:**
1. Open SQL Server Management Studio (SSMS) or Azure Data Studio
2. Connect to: `.\SQLEXPRESS`
3. If you can connect, SQL Server is running

If you **can't connect**, SQL Express might not be installed.

---

## 🛠️ Solution 3: Use LocalDB Instead

If SQL Express is giving you trouble, switch to LocalDB:

### Update Connection String

Edit `src/PowderCoating.Web/appsettings.json`:

**Change from:**
```json
"ConnectionStrings": {
  "DefaultConnection": "Server=.\\SQLEXPRESS;Database=PowderCoatingDb;Trusted_Connection=true;MultipleActiveResultSets=true;TrustServerCertificate=true"
}
```

**To:**
```json
"ConnectionStrings": {
  "DefaultConnection": "Server=(localdb)\\mssqllocaldb;Database=PowderCoatingDb;Trusted_Connection=true;MultipleActiveResultSets=true"
}
```

Also update `src/PowderCoating.Api/appsettings.json` the same way.

### Create Database

```bash
dotnet ef database update --project src/PowderCoating.Infrastructure --startup-project src/PowderCoating.Web
```

### Run the App

```bash
cd src/PowderCoating.Web
dotnet run
```

---

## 🛠️ Solution 4: Verbose Logging

Let's see exactly where it's hanging.

### Run with Detailed Logging

```bash
cd src/PowderCoating.Web
dotnet run --verbosity diagnostic
```

This will show you EXACTLY where it stops.

### Check the Log File

Look in: `logs/powdercoating-YYYYMMDD.txt`

The last line before it hangs will tell you what's wrong.

---

## 🛠️ Solution 5: Complete Clean Rebuild

Sometimes old build artifacts cause issues.

```bash
# From solution root
dotnet clean
rm -rf **/bin **/obj

# Restore packages
dotnet restore

# Build
dotnet build

# Run
cd src/PowderCoating.Web
dotnet run
```

---

## 📋 Diagnostic Checklist

Work through these in order:

- [ ] **Check console output** - What's the last line you see?
- [ ] **Is SQL Server running?** - Check the service
- [ ] **Can you connect to SQL Server?** - Try SSMS/Azure Data Studio
- [ ] **Comment out auto-migration** - Use Solution 1 above
- [ ] **Create database manually** - Use `dotnet ef database update`
- [ ] **Try running again** - Does it work now?
- [ ] **Check logs folder** - Look at the log file
- [ ] **Try LocalDB** - If SQL Express isn't working

---

## 🎯 Most Likely Issue

**90% of the time, the issue is:**

The app is trying to connect to SQL Express but:
1. SQL Express isn't running, OR
2. SQL Express isn't installed, OR
3. The connection string is wrong

**Quick fix:**
1. Comment out the auto-migration code (Solution 1)
2. Use LocalDB instead (Solution 3)
3. Run the app - it should start immediately
4. Create the database manually with `dotnet ef database update`

---

## 💡 Expected Behavior

### When Working Correctly:

```bash
$ cd src/PowderCoating.Web
$ dotnet run

Building...
Build succeeded.
    0 Warning(s)
    0 Error(s)

info: Microsoft.Hosting.Lifetime[14]
      Now listening on: https://localhost:7001
info: Microsoft.Hosting.Lifetime[14]
      Now listening on: http://localhost:5001
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
      Content root path: C:\Projects\PowderCoatingApp\src\PowderCoating.Web
```

**Then:** Open browser to https://localhost:7001 and you see the home page.

---

## 🆘 Still Not Working?

Share these details:

1. **What OS are you on?** (Windows, Mac, Linux)
2. **What's the last line you see** when running `dotnet run`?
3. **Is SQL Server installed?** How did you install it?
4. **What's in the log file?** (`logs/powdercoating-*.txt`)
5. **Does this work?** `dotnet ef --version`

With these details, I can provide more specific help!

---

## ✅ Quick Win

**Try this right now:**

1. **Stop the app** if it's running (Ctrl+C)

2. **Edit Program.cs** - Comment out lines 112-133 (the entire seeding block)

3. **Run the app:**
   ```bash
   dotnet run
   ```

4. **You should see:**
   ```
   Now listening on: https://localhost:7001
   ```

5. **Open browser** to https://localhost:7001

6. **You'll see an error** about missing database - that's OK!

7. **Stop the app** (Ctrl+C)

8. **Create database:**
   ```bash
   dotnet ef database update --project ../PowderCoating.Infrastructure
   ```

9. **Run again:**
   ```bash
   dotnet run
   ```

10. **Now it should work!** Navigate to https://localhost:7001/Identity/Account/Login

This bypasses the automatic migration that's causing the hang.