I just upgraded my son's business computer from Sandy Bridge to Z170.  After installing the motherboard drivers I keep getting Windows Boot Manager telling me to insert the installation disc and click "Repair your computer".  Done that a million times but keep getting the message to "Repair".  Message says "Info: The boot selection failed because a required device is inaccessible".  All cables are tightly connected.  Tried one stick of memory in slot 2 and manually adjusted voltage. No help.  At one point the message said that the Realtek driver was corrupted.
Thanks ahead for any help.
 
Mobo: EVGA Z170 FTW
Memory: 32 GB (8X4) EVGA Super SC
Power Supply:  CoolerMaster GX 750 watt.
OS:  Win 7 Professional
 
Forgot to mention that I am upgrading from ASUS P8 Z68-V Pro Sandy Bridge to EVGA Z170 FTW.  Could this be a conflict between the ASUS and EVGA motherboard drivers?  If so how can I fix it?
 

Assuming you're running Windows 7 read this:
 
http://www.pcworld.com/ar...ws_7_installation.html

Remove passwords  - or - (credential manager - make a copy & password reset disk )
Boot safe mode
Uninstall ALL old MB drivers
restart PC
Install new MB drivers
 
However after a couple of years Win 7 would benefit from a clean install.  At current prices -- I'd buy a new SSD for the OS.
 
Remove all hard drives install OS on to new drive -- then update
 
After ALL updates, then reconnect old drive to use as a data drive

Sometimes there are left over drivers causing a conflict. I have had to use CMD prompt to show hidden devices and delete the older chipset drivers and other such items.
Find all of your old drivers that are grayed out using this command, uninstall and check the box to delete the software:
Run Command Prompt as Administrator.

Type CMD in the search box, right-click CMD and select 'Run as Administrator'.

At a command prompt, type the following command , and then press ENTER:set devmgr_show_nonpresent_devices=1

Type the following command a command prompt, and then press ENTER:start devmgmt.msc

Troubleshoot the devices and drivers in Device Manager.

NOTE: Click Show hidden devices on the View menu in Device Manager before you can see devices that are not connected to the computer.

When you finish troubleshooting, close Device Manager.

Type exit at the command prompt.

I had no problems snagging the pictures and documents off of my sister's failed drive. I just plugged it into another SATA port and browsed the drive until I found what I needed and then used Copy and Paste to save everything to a USB flash drive. In her case it had some kind of infection that prevented me from doing anything with it incuding reinstalling the OS.

rjohnson11

Zuhl3156
I had no problems snagging the pictures and documents off of my sister's failed drive. I just plugged it into another SATA port and browsed the drive until I found what I needed and then used Copy and Paste to save everything to a USB flash drive. In her case it had some kind of infection that prevented me from doing anything with it incuding reinstalling the OS.

There are lots of free antivirus programs out there that do a good job of protection.
 
Once you have the data copied scan that data for viruses. if none are found and you have everything you need download the software tools from the hard drive or SSD manufacturers website and return that drive to factory specs preferably by running a series of digital 1 and 0(s) across the entire drive. Smells like a rootkit or a trojan. 

My sister's problem is that she never had any AV/AS software since 2004 when her PC was made. Malwarebytes found over 800 infections and several Rescue Disks found around a dozen rootkits that couldn't be removed. I thought it was in both of our best interests to get her a paid version of AVG with a 2 year license. I think she's good until April, I hope!

This tutorial might be easier to understand: http://www.thewindowsclub.com/show-non-present-devices-windows
Most of your issues will be under 'System devices'. This is where I needed to remove the chipset drivers when I went from my Z77 to my Z97 motherboard. The Intel Rapid Storage Technology version was also incompatible with the Z97 chipset. I suspect the same will be true for you.

Too late now, but keep in mind there is the Sysprep tool which is native in Win7/8/10 (Windows\System32\sysprep\sysprep.exe) which if conditions are met, can be used to:
• Change major hardware components (motherboard, etc.) but keeping old HDD(s).
• Move a HDD containing Windows to another computer.
• Make major hardware changes which would usually cause Windows to stop booting normally.
 
See: How to Transfer your Complete Windows 7 Installation to New Computer
 
Use Sysprep to prepare (generalize) your Windows installation to a hardware independent condition to be moved to a new computer, keeping all your installed applications, program settings and user profiles.
 
Never used it though as I've always just performed a Repair Install or Clean Install when making major hardware changes, just pointing out that Sysprep does exist and does exist for a reason.

F34R
Dude, different motherboard requires a fresh OS install. No idea why so many other suggestions are being made here when there's really only one correct thing to do. Don't buy into transferring OS from one to the other, it's asking for trouble :)

With Windows 7 many times a repair install can solve the problem. With Windows 8 and Windows 10 a fresh install is preferred.

I transferred the same installation of Windows 7 Home Premium 64-bit from an IDE install on a 750i SLI motherboard to an AHCI install on a P67 to a Z77 and then Z97 motherboard without too many problems except needing to activate over the phone. Maybe I just got lucky but lucky is better than spending three or more days downloading and reinstalling all of my software, games and tweaks. That's just my point of view from my experience. For those who insist on reinstalling their OS every year ot two I say .  Not happening in my house.

Best solution with this many problems since data is move and secured on another storage drive wipe main drive do a fresh install then move what data you need over to new install just basic stuff you dont want all the junk on there too that caused this issue in fist place