There have been reports that when upgrading the Bluetooth with
Enhanced Data Rate Software II for Windows 7 to version 184.108.40.2060 is
causing a wipe on the main OS drive (commonly C:\)
Affected units which uses this version of driver are as follows.
Support models ThinkPad L420, L421
ThinkPad T420, T420i, T420s, T420si
ThinkPad T520, T520i
ThinkPad X220, X220i, X220 Tablet, X220i Tablet
ThinkPad Edge E220s
ThinkPad Edge E420, E420s
ThinkPad Edge E520
Issue has been raised to engineering and the team are currently working on it.
****Please do not update the Bluetooth driver until further notice****
We are in a process of pulling the driver off the Support Site and ThinkVantage System Update
Main thread discussion here