Hello, how are you?
Welcome to the Microsoft Community!
My name is Paloma B., I'm an independent advisor, I'm here to help you in the best possible way.
I understand that you would like to remove Windows Startup Manager.
This happens precisely because you have two disks in your computer with Windows installed.
In this case I suggest that you format the HDD to remove the entire boot partition from the disk, so the Boot Manager will no longer appear.
If there is a need to backup the files, I believe it is not possible because you mentioned that you cloned the disk to a new SSD, this is excellent.
Follow the procedures below to format the HDD and keep only the SSD with Windows and boot properly.
First open the Command Prompt, press Windows + R, type cmd and click OK.
- In the Prompt type DISKPART, when it opens, DISKPART will appear on the left.
- Type LIST DISK, this command will list the hard drives installed on the machine, pay close attention not to choose the wrong hard drive.
- Type SELECT DISK “X”, in place of the X put the number for the HDD you want to format, put without quotes.
- Now just type the commands below and press Enter at each command.
- Commands:
CLEAN
CREATE PARTITION PRIMARY
SELECT PARTITION 1
ACTIVE
FORMAT FS=NTFS QUICK
ASSIGN
EXIT
I await news.
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