Sounds normal. You can research those messages for priors like http://en.community.dell.com/support-forums/laptop/f/3518/t/19649568 which many call out as a failing motherboard.
You might want to ignore this and save the bucks for a new laptop.
https://www.groupon.com/deals/gs-dell-latitude-e6400-laptop-intel-core-2-duo-4gb-ram-hdd-windows-10 pegs this as a 200 buck laptop when you can find them.
How about this 120 buck model which may have better specs? https://www.newegg.com/Product/Product.aspx?Item=9SIA6A35CV8466
There are folk that want a fix that doesn't require boards or such but the good news is this class laptop can be had cheaper than any repair counter.
We bought 2 of those for the office and used the last chance Windows 10 upgrade and these are neat for the bucks.
Hello,
I have a serious problem with my Dell Latitude E6400 laptop with Windows 10. Whenever I start or restart my computer now, the splash screen would display for a few seconds to complete the power-on self test (POST). After that, all I see is a blinking cursor, and that remains for about 50 seconds until Windows boots up which itself stalls for a minute before I get to the lock screen.
Whenever this happens, the Ethernet and Wireless adapters don't work, and when I go into Device Manager, the Wireless adapter is missing and these devices report errors:
http://i.imgur.com/pqHf8cl.png
The Wireless adapter was missing, and Device Manager reported the following errors:
1. Intel(R) 82567LM Gigabit Network Connection (Ethernet):
This device cannot start. (Code 10)
{Operation Failed}
The requested operation was unsuccessful.
2. Intel(R) Active Management Technology - SOL (COM4)
Windows has stopped this device because it has reported problems. (Code 43)
3. Intel(R) Management Interface
This device cannot start. (Code 10)
A device which does not exist was specified.
I began suspecting that it had to do with the Intel ME. I press F12 on boot, and select 'Intel Management Engine Boot Extensions (MEBx)'. I get something to the effect of "ME is initializing", it hangs on that screen for exactly 50 seconds, and then Windows boots (and hangs for 50 seconds).
I don't have any use for Intel ME, nor will I ever use it. I have had this problem intermittently for the past year, but I didn't pay attention to it until now. Re-flashing the BIOS didn't help; I couldn't update the ME firmware. It hung for 50 seconds, again.
http://i.imgur.com/t8xIZ2s.jpg
ME Firmware Update Failed! (Error Code: 8725)
-> Failed to receive last update status from the firmware.
I know something's wrong and unresponsive with the Intel ME, it's keeping my computer and network connections from working correctly and I don't have a warranty to take the PC back to Dell. What is going on???
Any suggestions would help.

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