RTM = Release to Manufacturing. I've always read it as Released to Market meaning it's "good to go" or stable. There are differences between Technical Preview (Alpha/Beta) and RTM. The link I sent him referred to a Tech preview which had the ability to do side-by-side installations. Which would of been the solution to his problem.
Windows 10 - Dual Boot with Windows 7 or Windows 8 - Windows 10 Forums
Hope it helps,
Williams
See Windows 10 - Clean Install - Windows 10 Forums
You need to boot the install media, not launch setup from a running Windows.
Step 7 enter your Win10 MSDN key
Step 10 ... there is a custom install - I've done it.
You won't have to clean the drive , but the partition should be unallocated / unformatted.
Delete the D:\ partition you created (D:\ = primary = to be used for Windows 10 to install Windows 10)
either in the custom step or before you begin the install
Then select the unallocated space in step 10 (you can shrink it later if it's too big)
Good luck ... it's easy
Ok, beats me how you'll accomplish this then. If it's a work PC, contact your IT department.
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