Windows8 prevents Windows7 from booting

  mniemann 16 May 13

I have Windows 7 Pro on the "production" PC and purchased Windows 8 to try it out. I installed Windows 8 on its own hard drive (and disconnected Windows 7 just to prevent any problems).

However, after installing and playing with Win8... it was time to do productive work. I disconnected the Win8 drive, re-attached the Win7 drive, and attempted to reboot. Some Win8 boot message is displayed saying "a drive is unavailable" with no other useful options.

So clearly unplugging the drive is not enough! Can anyone enlighten me as to what is happening so I can understand how to make the two boot drives peacefully coexist? Clearly the BIOS is involved in some way, even though I have not "enabled Windows 8 support" in my MSI MS-7751 motherboard.

Regards, Mike N

  woody 16 May 13

Are they both normal HDD? I have done exactly as you have done - win7 on a drive working normally - unplug win7 - load win8 works perfectly and then unplug win 8 and plug in win 7 works perfectly BUT only when they are both internal HDD.

  woody 16 May 13

Why not use dual boot?

  mniemann 17 May 13


Both are internal SSD's... and I do not have "hot swap" enabled.

As to your dual boot question, that is what Windows 7 recovery set up as the "recovery" solution. So now I have to keep both drives connected at all times. So I have a workable solution now.

But my question was more about "why" and "how" does Windows 8 screw up booting from a drive that wasn't even connected when it was Win8 was booted / running???

Regards, Mike N

  woody 17 May 13

I use SSD,s but only one in my test rigs plus other HDD. It may be the way you have configured the "BIOS" . I do not have a test rig with two SSD,s so can help - good luck.

  woody 17 May 13

Should be -"can not help" sorry.

  rdave13 17 May 13

Do you have a 'normal' BIOS or 'UEFI' or a hybrid? It will be something to do with secure boot I think.

  mniemann 20 May 13

I have a UEFI bios, but as I said I do not have "Windows 8 support" enabled... which I took as Secure boot + other stuff.


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