Thank you for your message. I am sorry that there are problems getting the Plugable Bluetooth adapter working well in Windows 7. I would like to help.
In some cases, it is feasible to disable the built-in Bluetooth adapter and install our adapter along side it, but this is not always the case. Truly removing the software for built-in adapters can be difficult if Windows automatically installs the device again prior to being disabled. When Windows is aware of multiple Bluetooth adapters, it does not handle this situation gracefully and often results in conflicts with the Bluetooth software in Windows.
Typically the best way to fully disable the built-in Bluetooth is by turning it off in the BIOS, if your computer supports doing so. From what I have seen it is likely possible to do this on the Lenovo T520.
Try disabling the built-in Bluetooth in the BIOS. If this is not available, or does not help, could you run our diagnostic program? It will gather device information and installation logs that will help me understand what is happening.
To do this, please have the adapter plugged into your computer, then go to this page and follow the instructions there:
Once you have the log, please send it to us via e-mail at email@example.com with the subject “For #150282”.