Method 1: Check the steps listed below and see which one helps you:
Step 1: If the Bluetooth icon is not in the notification area, you can enable it by following this step:
a. Click Start, click Run, typebthprops.cpl, and then click
OK. To use the bthprops.cpl command, make sure that Windows XP SP3 supports your Bluetooth adapter and the Bluetooth adapter has been successfully installed on your Windows XP SP3-based computer. You will now get
the Bluetooth Devices window.
b. Click the Options tab,put a tick in the box next to
Show Bluetooth icon in notification area.
Step 2: Alternatively you can try this step as well to enable Bluetooth icon in notification area.
You can also right click in the empty space in the taskbar and in the notification area you can press on customize. This will allow you to set each icon to hide if inactive or show if active.
Method 2: Here’s a post which addresses similar issue as yours. Check the link below which has potential steps to fix the issue.