There are two ways to do this:

1. Editing the product directly via the product editor, or
2. Importing a spreadsheet (bulk update).

Using the product editor:

1. Go to Products > Products / Sku variations.
2. Open/edit the product by clicking on it.
3. Click the toggle labelled Has serial numbers to turn the feature on/off.
   
4. Click Save.

Using a spreadsheet import (bulk update)

1. Export the current list of products into a spreadsheet.
   1. Go to Products > Export data.
   2. Select the data type Products and ensure you include all available columns in your spreadsheet to download.
   3. Click Download.
2. Edit the spreadsheet.
   1. In the Has serial numbers column, enter yes for each product you want to enable the setting for (leave blank or enter no to disable).
   2. Save the file.
3. Import the updated file.
   1. Go to Products > Import data.
   2. Select the data type Products and upload the updated spreadsheet, then save.

Serial numbers can be captured during two processes:

1. Receiving purchase orders
2. Ship out / dispatching sales orders

To enable serial number tracking when receiving purchase orders:

1. Go to My account > Settings > Purchases > Options.
2. Click the toggle labelled Capture serial numbers to turn the feature on/off.
    
3. Click Save. Once enabled, during the purchase order receiving process you'll be prompted to scan or enter serial numbers for each serialised product.

To enable serial number tracking when shipping out / dispatching sales orders:

1. Go to My account > Settings > Sales > Options.
2. Click the toggle labelled Capture serial numbers to turn the feature on/off.
    
3. Click Save. Once enabled, during the sales order dispatch process you'll be prompted to select or enter serial numbers that match the quantity being shipped.

Yes. Here's how you can do this:

1. Go to Sales > Sales orders.
2. Open/edit the order by clicking on it.
3. Click Ship out & invoice > Pre-enter serial nos.
4. Select a product line (highlighted with a red arrow).
5. Scan or enter serial numbers, or click View serial nos to select from a list of available ones.
6. Continue to the next line until all product lines are completed.

There are two ways you can view them:

1. From the serial numbers page (Products > Inventory control > Serial numbers).
2. Under the serial numbers tab when viewing any product page.