Right click on Bluetooth icon in task manager > Add a Device
Select ELM327 Bluetooth device. It'll come under different names like: OBDII, OBD-II, VLink, Can OBDII, etc.
NOTE: It can take up to 15 seconds for Bluetooth signal to show.
SIGNAL NOT SHOWING?
If signal does NOT show, then exit the screen. Disconnect ELM327 Bluetooth from car. Then insert it again into car's port, and do another "Add a Device".
If signal STILL doesn't show, then restart computer, and do another "Add a Device". Repeat these suggestions in variations until signal eventually shows. Because as long as the red Power light is lit on the ELM327 Bluetooth device, it means it's physically working, and MUST be detected.
WORD OF CAUTION: Any attempt to detect ELM327 Bluetooth after pairing it for the FIRST time — may NOT show inside "Add a Device" anymore. In this case, it's found inside "Show Bluetooth Devices".
When you see list of pairing options like this:
(For Windows XP users, your option will be: Use the passkey found in the documentation)
If OBD software has trouble connecting to your car, then set baud rate of connection to: 9600 or 110. Hopefully the software you're using has this option inside it's Settings. For example TOAD software has option to force 9600 bits per second, which instantly fixes random disconnection issues.
If your OBD software doesn't have option to limit connection speed, then you can also limit it through Windows settings. Here's how...
Go to Device Manager > and expand "Ports (COM & LPT)".
Control Panel » System » "Hardware" tab » Device Manager » Ports (COM & LPT)
Control Panel » System » Device Manager » Ports (COM & LPT)
Right-click on "Standard Serial Bluetooth" (it may be a different name for you) > Properties
Go to "Port Settings" tab > Lower "Bits per second" to 110. Click Ok. As seen below. Then attempt to reconnect to your car inside the OBD software.