There's no need to erase your hard drive to install the preview of Windows 10. And certainly there is no need to remove the recovery drive. Just shrinking your current c:\drive and installing Windows 10 in a the free space suffices to get a dual boot configuration. See http://www.howtogeek.com/197647/how-to-dual-boot-windows-10-with-windows-7-or-8/
But it could well be that installing Windows 10 changes the boot sector in such a way that you can't reach the recovery partition anymore. Then you would need the recovery disks indeed.
Kees
Hi,
I need to completely erase my hard drive to install the preview of windows 10. Therefore removing the recovery drive. If I was to do this, would I still be able to recover my OS using the recovery disk what came with the PC?
Thanks
Dylan

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