Dual booting Windows 7 64 and 32 bit - reversible?

[ngom52]

Hi everyone,

I currently have windows 7 home premium 64 bit installed on my pc. I've had some issues running matlab in a 64 bit environment so I'm planning to also install a 32 bit windows 7 professional.

If in the future I were to format the partition/drive containing the newer installation (32 bit windows 7 professional), will this mess up the bootloader, or cause any other problems to the older installation? I once installed xp after W7 and as a result of that installation I can no longer boot to W7...........

Thanks in advance!

 

[Bolbi]

I believe that the Win7 bootloader is the same for both 32-bit and 64-bit. So if you reformat, the same bootloader will still be there. Then you can go back into your first installation (Win7 Home Premium 64-bit) and edit Boot.ini (Start>Run>msconfig, "Boot.ini" tab) to remove the entry for Win7 Pro 32-bit.
The problem you had with installing XP after Win7 is because XP has an older bootloader that is not compatible with the new way booting is handled in Vista/Win7. Thus, it does not recognize Win7. (Just for the record, this incompatibility is not two-way. Win7's bootloader does recognize older versions of Windows.)
Hope this helps!

 

[The_Prophecy]

I believe that the Win7 bootloader is the same for both 32-bit and 64-bit. So if you reformat, the same bootloader will still be there. Then you can go back into your first installation (Win7 Home Premium 64-bit) and edit Boot.ini (Start>Run>msconfig, "Boot.ini" tab) to remove the entry for Win7 Pro 32-bit.
The problem you had with installing XP after Win7 is because XP has an older bootloader that is not compatible with the new way booting is handled in Vista/Win7. Thus, it does not recognize Win7. (Just for the record, this incompatibility is not two-way. Win7's bootloader does recognize older versions of Windows.)
Hope this helps!

+1. Additional installs of Windows 7 will detect an existing instance of bootmgr and will add new entries to it accordingly. Vista will do the same. XP was different because, as Bolbi said, XP used the boot.ini file for referencing installs of operating systems whereas Vista and 7 use bootmgr.