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Windows 7: 0x80300021 install error Windows 7 Pro Dual Boot

25 Nov 2015   #1

Windows 7 Home 64 bit, Wndows 7 Po 64 bit
0x80300021 install error Windows 7 Pro Dual Boot

0x80300021 install error Windows 7 Pro Dual Boot
I have a system with two hard drives for a dual boot system.
I swapped out the two hard drives for larger ones.
I installed Windows 7 Home on the first hard drive and everything worked fine with no problems.
When I went to install Windows 7 Pro on the second hard drive, I keep getting the 0x80300021 error message and I can not install the window 7 Pro OS. The second drive is formatted and checked for errors.
See attachment for disk layout. I am trying to load Windows 7 Pro on Disk 1 7-PRO (P drive)

Attached Thumbnails
0x80300021 install error Windows 7 Pro Dual Boot-disk-management.png  
My System SpecsSystem Spec
25 Nov 2015   #2

Windows 7 Home Premium 32-Bit - Build 7600 SP1

Why are you installing two Win 7's on your PC? It does not serve any purpose and you are legally supposed to have two Product Keys to do this.
My System SpecsSystem Spec
03 Dec 2015   #3

Windows 7 Home 64 bit, Wndows 7 Po 64 bit

I have two separate product keys with 2 separate install disks.
One is for Windows 7 Home and the other is for Windows 7 Professional.
I do a lot of testing on the Windows 7 Home system and when it works properly, I load it on the Windows 7 Pro drive.
Also on the Windows 7 Home disk, I run Windows XP mode that I can not run on Windows 7.
My System SpecsSystem Spec

03 Dec 2015   #4

Windows 7 Pro x64 Windows 10 Pro x64

Why didn`t you unplug Disk 0 before you attempted the install on Disk 1 ?

You`d still have a dual boot and better control over it.

If you swapped out the drives, how did you end up with a recovery partition on Disk 0 ? Did you clone it ?

Where did the Windows 7 Pro installer come from ?

Did you create it, it could be bad, just need to create a new one.
My System SpecsSystem Spec
07 Dec 2015   #5

Windows 7 Home 64 bit, Wndows 7 Po 64 bit

The first time I loaded Windows 7 Pro, on 2 separate drives it loaded with no problems without unplugging Disk 0.
The HP Recovery is a copy of the OS that I copied from the original CD for a backup.
The Windows 7 Pro is a OEM disk from Microsoft.
I will try unplugging Disk 0 to see how it works.
Does the Original "C" drive letter change when I plug the Disk 0 drive back in?

Unplugged Drive "0' Worked fine.

My System SpecsSystem Spec

 0x80300021 install error Windows 7 Pro Dual Boot

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