We have a laptop that on occasions will not boot. There is fan activity and powered led are on but no bioís image,. It will then close itself off and after some time will boot.

The maker asked for windows logs and the system one does record a lot of HD controller errors for disk 2 and 3. These are in 1, 2 and 3 together and also larger blocks of 8-10. In the latter its a mixture of drive 2 and 3. So they have got it back. Now they say they can find nothing wrong and the errors are an external USB HD.
Most of the time the laptop is used with a USB docker and the data files are on a server. There is no directly attached HD. The currently networked laptops do not have the same problem and the sever has no HD errors in its logs.
I would be grateful for advice as I canít see how an external, if there was one, errors to a server HD could result in log errors when the laptop if wiring via Launchpad with folders. I also do not see how an external error could prevent the bios running.

The error is below but as the laptop doesn't boot these clearly it can't be loging actual failure to boot.
Log Name: System
Source: disk
Date: 24/11/2016 19:38:06
Event ID: 11
Task Category: None
Level: Error
Keywords: Classic
User: N/A
The driver detected a controller error on \Device\Harddisk3\DR11.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
<Provider Name="disk" />
<EventID Qualifiers="49156">11</EventID>
<TimeCreated SystemTime="2016-11-24T19:38:06.673917100Z" />
<Security />
<Binary>0F00800001000000000000000B0004C003010000000000000000000016000000000000000000000058E57B000000 0000FFFFFFFF06000000580000050000000000000612280108000000000073000000000000000000000080D8B76702A9FFFF 00000000000000001010E36802A9FFFF000000000000000000000000000000001B0000000100000000000000000000000000 00000000000000000000000000000000000000000000</Binary>