Following an update from an earlier version of BIOS to version 22, Bluetooth on my IdeaPad S205 stopped working.
The BT was not active at the moment of my bios update but it was perviosly seen correctly in system, but now hasdisappeared. I have tried going into BIOS and setting to activate but have been unsuccessful.
This was found to be a bug in BIOS versions 22 and a new BIOS for Ideapad S205 is available here BIOS 24
Use of BIOS 24 or later should resolve the issue.
Despite best efforts during testing, new releases may sometimes create incompatibilities in prior features / functions and users may wish to return to a previous BIOS level to restore that feature while further updates are developed by Lenovo.
The winphlash utility used to update BIOS contains a backup feature to allow users to restore a previous version. A BIOS.BAK file is created during the update process and saves your previous installed BIOS to the HDD in a flashfolder c:\winflash
You can then rename the BIOS.Bak as a different file name and re-run winflash and specify the new filename (here shown as BIOS1.WPH in the example screen shot below. This would then flash your BIOS back to the prior level and save the current (in memory) BIOS image as BIOS.BAK