I have posted this info in a few previous threads but for those that can't find it, I'll post it again.
Configuring the Broadcom 2045A Bluetooth Dongle in Windows
If your bluetooth dongle shows up as a BCM2045A under Other Devices in Device Manager, there’s an easier way to configure it without having to install its bulky driver from the CD you got. And if you didn’t receive a CD with your BCM2045A Bluetooth Dongle, this guide is definitely for you.
Tested on: Windows XP Professional and Windows Vista Ultimate.
First, connect the device to the computer via USB as usual. Now Windows will tell you installing the new hardware has failed and so on, not even Windows Update can resolve it. This is typical of Windows as it doesn’t have the required drivers for this particular Broadcom BCM2045A Device.
Now right-click on My Computer and hit Manage. From the window that pops out, click Device Manager on the left side-pane. You must see the ‘BCM2045A’ written in it under the section ‘Other Devices’. Right click that and hit Properties now. Go to the details tab and from the drop down menu that appears, select Hardware ID. You should see two lines that look like below:
Right click the second one (Without the REV* thing) and select Copy.
Now head to My Computer and under the Windows directory, enter the directory named INF (or inf) and locate the bth.ini file in it. Open the bth.ini file with your favorite text editor (I prefer the vanilla Notepad), and find the line called “Device Section Start” in it.
Note: Its okay if you cant find the device ID (Hardware ID), Hit C:/Windows/inf/ in the explorer and find bth.ini it’ll be there for sure if its a good copy of Windows.
Now locate the name ‘Broadcom‘ and under it, you’ll see a device of BCM2033 or so with a different Hardware ID. Just replace the 2033 with a 2045A and the 2033 in the Hardware ID line (Something like “Transceiver= BthUsb, USBVID_0A5C&PID_2033“) with 2045 in place of 2033. Else, just erase the USB/VID line and paste the one you had earlier copied into the clipboard.
Save the file and quit.
Now replug the device and go to Device Manager again via My Computer - Manage. Find the BCM2045A again and right click and choose Update Driver. When Windows offers to search for drivers for the 2045A ask it to show you a list of known hardware to choose manually. Now look for Bluetooth Radio devices and under that look for Broadcom.
Under Broadcom, choose the one that has 2045A (i.e, the one we edited. It may still show up as 2033, but still, select it!) And hit next. The devices will now be found, installed and configured. Thus, you dont need to install the crappy drivers from the CD unless you’re in love with it…
P.S. Next time, don’t buy a cheap hardware like this BCM2045A ones. Its better and easier to use a known and popular device even if they cost a few bucks extra. Or you can consider going in for Ubuntu OS rather.