cl500man

Hi guys i am new to this forum...i have recently purchased a 2007 cl500 w216... The only window that works is the driver side window.... I have replaced the battery as i kept on getting the battery warning light....(and its still coming on)... I took it to a mercedes specialist who had the latest diagnostic tool (star) and it cam dup saying rear sam permanent error.... so i replaced it and still tno joy.. we have also checked all the fuses...has anybody else had this problem?? if so what was the problem... please share .. many thanks...