[hassle] SSD migration, windows 10

I bought an SSD recently and tried to migrate my system.  However, no matter which tools I used(Clonezilla, DiskGenius), they both failed to boot, with a black screen only have an spinning cursor on it.

After a day of hassle, I found the solution.

Just ignore any advice to use bootrec, we can now use the bcdboot command which is more automatic and trouble-free.

1. Get to winre, run regedit
2. select hklm anyfolder, open hive -> c:\windows\system32\config\system, type any name
3. use diskpart to assign correct drive letters
4. delete all driver letters under the hive, except the one you need
5. copy value of dosdevice* from hklm->system->mounted volume to the hive of same subfolder

Now, the drive letter problem is fixed.  Let's fix boot.

6. assign letter to the efi partition
7. do bcdboot /help, follow the instructions

8.  finally can re-enter windows now.