Dell Latitude 10 docking station MAC issues

We experienced some problems with Dell tablets that had docking/charging port issue.
This became a bigger issue, more tablets were getting this problem.

So the plan was to swap out the 2 docking stations we had.
These were swapped at the same moment.

A few weeks after the swap we noticed issues on the network.
As this issue was not exposing itself  right after the swap ,we did see the connection.

But after testing the docking stations at another location by my colleague, we were still clueless.
The day after his return we put the docking station on the desks again.
My colleague just took some network cables to connect them again.

This is where we found out that something was wrong.
We had already had a separated the dockings on another VLAN.
This was to check if it was the IP phones that were messing up the network connection or something else.

Our network guy came in looking for 1 device making requests on 2 different VLANs at the same time ????

After checking the MAC addresses in our cubicle we found the dockings had the exact same MAC address….

Just speechless and baffled by this occurrence we logged a ticket with our service provider whom was doing the dell repair services.

He logged a ticket with Dell…
Four months passed…
After reading the info through out the ticket, i was even more baffled.
5 docking stations where send to them…. ALL had the SAME MAC ADDRESS.
Dell technicians could not figure out why this was the issue .
The handling time for this issue was already over 4 months.

I had enough after reading the ticket : “this is a Windows driver issue, Dell is creating a ticket with microsoft”…
So i got really mad and frustrated.

So you work for Dell as a technical advisor and don’t know that a MAC address is given by the hardware (EEPROM from the chipset) ????
Then dare to state that the MAC address is given or contracted from a driver.

We really needed the Docking station working again with a correct MAC address.
Otherwise the backlog on a new fresh image was getting bigger every day.

So i went on a Google search journey…
It took me 35 Minutes to find out that the things that i needed to know.

So in one of the paragraphs the manufacturer states that you can only write to the EEPROM of the chipset if you have installed a specific driver.
This driver is not eligible for distributing among end users ( aka -> ME )

 

If you would do this with the normal driver or the one provided with windows update(driver) you would render the chipset to a brick.
After a break outside  i remembered some things from the driver hacking videos and  thought i would be able to pull it off.

Worst case scenario i would still end up with a docking station that needed to be replaced as there was already a replacement planned if they found the issue …

Still we are 35 minutes in this …
After looking for some recent drivers for this on the all mighty friend google i found these.Now i installed these to test the tools i got from Microchip.com.
This did not work all i got was “Device not connected”
Or “READ_REGISTER failed!”Now i had spend 55 minutes into this case.
I decided to take advantage of the knowledge of glitching the driver install.
Something i picked up a long time ago watching the Hacking videos from DEF CON , HAK5 , etc …

To glitch the driver and being able to write to the EEPROM you need to install the drivers again.
Again you say, come on really ….not kidding .
But you need to do something different when installing “Do not click the OK button”.

This gives you a time frame that you can communicate with the device without the driver that was first unloaded and then installed again would not be loaded again.
it only loads when you click “OK” (screenshot in Dutch, sorry)

If you would try to communicate with the chipset you actually can without an error.
But first configure the INI file to get another starting MAC Address (this is the address that your unit is getting).
These tools are for mass production and can do the counting upwards if you plan on doing more EEPROM flashing then that one docking station.
So chose a MAC that is not in your network….

After this is set you can run the tool provided by Microchip.
7500eepapp.exe –w –i 7500eep.ini

And after 1 hour success: the current device was programmed

I got the new MAC address:

Hope you enjoyed the Blog story.