If the official route doesn't work, your laptop likely uses a Broadcom chipset (very common in this model). You can download the generic Broadcom Bluetooth driver.
He spent hours in the trenches of legacy forums. He read threads from 2011 where users argued over ID strings and compatibility modes. He felt like an archaeologist brushing dust off a digital fossil. Finally, on a mirrored site hosted in a corner of the internet that time forgot, he found it: Broadcom_Bluetooth_v6.2.0.9600_Win7.zip. acer aspire 4730z bluetooth driver windows 7
Once installed, check: