Windows 10: Windows file encryption on old user account

Hello, I encrypted some important files on my old Windows 10 install and I unfortunately had to reistall Windows because it wouldn't let me just upgrade to Windows 11. Now that I have a new user account I am no longer able to access those files. The files were encrypted with the basic built in encryption in Windows. Can anyone help? Thank you for your time.

:)

 

Windows XP file encryption

LOL thanks, I think its standard windows XP file encryption

 

windows 7 encryption problem

I'm pretty sure that those files contents are unrecoverable. On Windows the key needed to decrypt the files content is stored on the user account definitions (one for each user, so that one user can't access other user files), so as soon has the original account that encrypted the files was deleted, those files became nothing more than a pile of bits.
I might be wrong but this is what I remember from the Windows security system.

 

Software encryption

read this:
The Encrypting File System (EFS) is a file system driver with filesystem-level encryption available in Microsoft Windows (2000 and later) operating systems, except Windows XP Home Edition, Windows Vista Basic, and Windows Vista Home Premium. The technology transparently allows files to be encrypted on NTFS file systems to protect confidential data from attackers with physical access to the computer.

User authentication and access control lists can protect files from unauthorized access while the operating system is running, but are easily circumvented if an attacker gains physical access to the computer. One solution is to store the files encrypted on the disks of the computer. EFS does this using public key cryptography, and aims to ensure that decrypting the files is in theory impossible without the correct key. However, EFS is in practice susceptible to brute-force attacks against the user account passwords. In other words, encryption of files is only as strong as the password to unlock the decryption key.

read more ...wikipedia Encrypting File System - Wikipedia