Create a backup key for the encrypted NTFS partition

If you have NTFS partitions on your hard disk and the data in the partition is encrypted, you should create a backup key, just in case. The key creation method is as follows.
Click "Start> Run", enter "certmgr. msc" in the displayed dialog box, and press the Enter key to open the Certificate Manager. Under the "current user → personal → Certificate" branch, we can see a certificate named by your user name (if you have not encrypted any data on the NTFS partition, there is no certificate here ). Right-click the certificate and select the Export command under "all tasks. The certificate export Wizard will be opened, and then click "Next" as prompted until the wizard asks you if you want to export the private key and select "export private key". All other options will retain the default settings, finally, enter the user's password and the path you want to save and confirm the export. The exported certificate is a file suffixed with PFX.
 
After porting or reinstalling the operating system, find the PFX file, right-click it, and select "Install PFX". An import wizard is displayed, follow the instructions in the import Wizard to read the files in the previously encrypted NTFS partition.
Note that if you do not have a backup key and you need to reinstall it in case of an operating system problem, you cannot access the encrypted data on the NTFS partition with the same user name. Only the backup key can be imported to correctly open the previously encrypted data file. To compress a partition, decompress it as required by Windows.

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