Announcement

Collapse
No announcement yet.

HP Elitebook 840 G2

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    #21
    HP Elitebook 840 G2: Flash BIOS to clean password

    Hi

    I picked up a heavily damaged laptop from a friend who had basically screwed it over. I've fixed most of the bits but now I need a way to remove the BIOS password that he forgot the password to. I knew this before I got it but thought I could get around it.

    I can read and write the chip on the motherboard using a SOIC clip and my pi and reading certainly seems consistent.

    I've dumped the current BIOS as a precaution but all I want to do is effectively replace the current with a BIOS version that is not protected. Is someone able to look at the rom file and remove the password protection?

    Thanks,

    Chris

    Comment


      #22
      Re: HP Elitebook 840 G2: Flash BIOS to clean password

      Upload the original dump here. then, the other members will be able to help you more.

      Comment


        #23
        Re: HP Elitebook 840 G2: Flash BIOS to clean password

        Cool thanks. Posted below. I've MD5 checked summed 3 pulls from the chip and they all matched the hash so I'd say it read correctly.
        Attached Files

        Comment


          #24
          Re: HP Elitebook 840 G2: Flash BIOS to clean password

          Originally posted by Benoire View Post
          Cool thanks. Posted below. I've MD5 checked summed 3 pulls from the chip and they all matched the hash so I'd say it read correctly.
          If you remove password post 16mb bios file.The password store 16mb pch bios.

          Comment


            #25
            Re: HP Elitebook 840 G2: Flash BIOS to clean password

            Sorry, I'm new to chips in this manner... I'm not sure what you are trying to say. What I was stating was that I had read the BIOS chip 3 times and saved as 3 different file names to ensure that the connection was not corrupting the read; i.e. that reading the chip was stable enough to access it properly... The 3 files had the same hash which suggests that the reading was stable enough.

            Comment


              #26
              Re: HP Elitebook 840 G2: Flash BIOS to clean password

              I think this motherboard have 2 bios chip find bios chip (Winbond 25q128bv/fv).which programmer you have use?

              Comment


                #27
                Re: HP Elitebook 840 G2: Flash BIOS to clean password

                Erm it was a soic clip and then a raspberry pi with SPI enabled to access the chip. There are two chips on the back below the cover which are exposed. I could try and get a reading of the other one and see if that has something?

                Comment


                  #28
                  Re: HP Elitebook 840 G2: Flash BIOS to clean password

                  ok, so got it reading the other chip which wasn't being recognised... Was a commandline setting in flashrom which is required for the pi.

                  Ran the read command 3 times and md5 hash was the same so this should be a complete dump of the bios image.

                  The image size was 16mb which appears to be the right size as what you suggested.
                  Attached Files

                  Comment


                    #29
                    Re: HP Elitebook 840 G2: Flash BIOS to clean password

                    Originally posted by Benoire View Post
                    ok, so got it reading the other chip which wasn't being recognised... Was a commandline setting in flashrom which is required for the pi.

                    Ran the read command 3 times and md5 hash was the same so this should be a complete dump of the bios image.

                    The image size was 16mb which appears to be the right size as what you suggested.
                    Try this and reply.
                    Attached Files

                    Comment


                      #30
                      Re: HP Elitebook 840 G2: Flash BIOS to clean password

                      Thanks. Tried this but it was unsuccesful, the flashchip won't erase. It is stating that block protection is active but I'm not sure how to get rid of that on the device. I know that HP Chromebooks use a write protect screw, but I'm not aware of the 840 having something similar.

                      Comment


                        #31
                        Re: HP Elitebook 840 G2: Flash BIOS to clean password

                        So it looks like it might be HP Sure Start in action. On booting, the laptop indicates a checksum error and then restarts with the old bios as configured. Any further thoughts on this?

                        Comment


                          #32
                          HP EliteBook 840 G2 Unlock my bios pleas

                          HP EliteBook 840 G2 Unlock my bios pleas
                          Attached Files

                          Comment


                            #33
                            Re: HP Elitebook 840 G2

                            Hi all, this is just the thread I've been looking for!!!
                            I have an Elitebook 840 G2 with BIOS password. I tried HP support, they supplied SMC.BIN reset but it did not work,.. I suspect because system date is way off (previous owner removed RTC..?)
                            Anyway, I'd really like to have a go at reprogramming the IC (its a Winbond 25q16dvsig)
                            I'm about to buy a TL866CS and a Pomona SOIC8 SOP8 Chip IC Test Clip Adapter so I can read (and write) to BIOS - is this the correct kit?
                            Then I can use the above file posted by imranromi (hp 840 g2 backup bios bin CLEAR PASSWORD.zip (9.32 MB)) and flash the chip,.. and,.. hopefully be OK?
                            I guess I'm asking if that is the right hardware to buy and have I got the basic plan to fix this understood?

                            Many many thanks!!!!

                            Comment


                              #34
                              Re: HP Elitebook 840 G2

                              So, I bought a TL866ii plus programmer and WINGONEER SOIC8 SOP8 Test Clip - got latest software from manufacturers site - all installed, latest FW on programmer. I have removed the mobo & RTC battery as well. At this point I thought I was almost there,... but for a few hours now I've been stuck just trying to read the chips... In this case I have 2 chips - a 16MB Winbond 25Q16DVSIG /1526 and a 2MB MXIC25L12873F. If I understand correctly I need to read the 16MB chip and then write a password free bin file back to it..? SO, at the very first hurdle I have a problem just reading the chip... I keep getting error/alert message "Overcurrent Protection actions! External short circuit/IC reverse or damaged!"... I also have a 2nd board to test on too, and I'm getting same error again and again. Have tried all the 8 pin variants in IC selection (plain, SOIC8, OTP etc..) all give same error and a "Pin detecting Passed!" status. Have I got the right kit to read/write to these chips (in circuit)? What am I missing - I assumed it would read and I could save the dump and post here for guidance, but I can't even read the chip..? ANy help much appreciated!!

                              Comment


                                #35
                                Re: HP Elitebook 840 G2

                                try to flash out of the board

                                Comment


                                  #36
                                  Re: HP Elitebook 840 G2

                                  Originally posted by imranromi View Post
                                  If above not works try this.

                                  Could you help me with my HP 840 G2? What i should post here? My SN number or what? Thanks

                                  Comment


                                    #37
                                    Re: HP Elitebook 840 G2

                                    I have a hp 840 g2 with administrator password can someone help remove it?
                                    Attached Files

                                    Comment


                                      #38
                                      Re: HP EliteBook 840 G2 Unlock my bios pleas

                                      Originally posted by Japanac View Post
                                      HP EliteBook 840 G2 Unlock my bios pleas
                                      How did you dump your BIOS into bin file?

                                      Comment


                                        #39
                                        Re: HP Elitebook 840 G2

                                        Originally posted by kamien77 View Post
                                        Could you help me with my HP 840 G2? What i should post here? My SN number or what? Thanks
                                        Here is my current BIOS backup with this password
                                        Attached Files

                                        Comment


                                          #40
                                          Re: HP Elitebook 840 G2

                                          can you help me this is my bios backup for elitebook 840 G2 , i want to remove the password

                                          Comment

                                          Working...
                                          X