There should be no yellow exclamation marks.
This is the core of your problem. There is no official "MBT-503-03" website because this is a generic chipset used in dozens of unbranded dongles. The solution is to install the or the Generic CSR 4.0 Driver . Bluetooth mbt-503-03 driver windows 7
working on Windows 7, the community has found a few "deep" fixes that feel like digital archaeology: The Vista Workaround : Many users found success using Windows Vista 64-bit drivers There should be no yellow exclamation marks
Once you've downloaded the driver, follow these steps to install it: Bluetooth mbt-503-03 driver windows 7
: Many of these dongles utilize a CSR (Cambridge Silicon Radio) chip. For these, a CSR-specific driver may be required to enable advanced features. Installation Guide To install the driver manually via Windows 7: