Changing C: drive letter of installed Windows problem


Active Member

I want to change Windows drive letter C:\ to another (in my case W:\).
We all know that it is not possible by easy way, but some tutorials I found, but three times installed Windows 10 Pro it failed.

Here's what I was following:

Start Regedt32.exe as admin
Select Permissions - Verify that Administrators have full control
Quit Regedt32.exe, start Regedit.exe
Find the drive letter you want to change to (new) \DosDevices\C:
Rename \DosDevices\C: to \DosDevices\Z:
Find the drive letter you want changed. Look for \DosDevices\D:
Rename it to the appropriate (new) drive letter \DosDevices\C:
Value \DosDevices\Z: rename back to \DosDevices\D:
Quit Regedit, and then start Regedt32
Change the permissions back to the previous setting for administrators. It should probably be Read Only

Really I see that it looks like these steps:

login as admin (I have single account and it is admin)
start regedt32
confirm admin permissions to full control
start regedit
enter HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices (here I see that not matter if I open regedt32 or regedit it has selected the same key)
rename \DosDevices\C: to \DosDevices\Z: (Z is temporary)
rename \DosDevices\D: (or selected which will be C:) to \DosDevices\C:
rename \DosDevices\Z: rename to selected letter, e.g. \DosDevices\W:
start regedt32
set admin permissions back to the previous setting (never was change)

Last time I tried to change also system variables - and it bit helped, but finally not success.
When I did not changed system variables it was always hanging at boot.
When I changed system variables, it at least breaks to BSOD.
I changed system variables by command line. Is it enough or it needs also modify registry items (I know where they're located)?

Where do I the mistake?

Thank youall for each help, replyor comments.



Cloud Security Engineer
Staff member
I have to ask why would you want to do this? Also you're likely to break every program on the computer and anything else that has paths hard coded.


Active Member
Purpose is to leave run software specific for non-standard tasks and also to leave running 16-bit DOS/Windows applications in default mode by NTVDM64.
I have no problem to apply all pissible waysm I know that talking that, evelrno