Hello,I have the following problem: Due to problems with the Windows 1809 Update, I had to completly reinstall my Windows 10. On my old Windows 10 OS, I had some files which I encrypted (right-click on file - properties - advanced - encrypt contents to securedata).

• How To Access Encrypted Files

I have a whole backup of the encrypted files and my old C: drive, but I forgot to decrypt them. Is it possible to decrypt them now? I think I have to import some keys which are stored on the old C: drive, but I don't know how to do that or if it'sthe right way at all.thanks for any helpmoved to English language forums.

Step 2: Insert a Bitlocker encrypted drive. Step 3: Select Bitlocker encrypted drive and then click 'Open' icon to unlocker. Step 4: Enter the password to unlock the Bitlocker encrypted drive. Step 5: After unlocking, the Bitlocker encrypted drive will be mounted in read-write mode, we can copy files out or write new data.

HiMy name is Andre Da Costa; an Independent Consultant, Windows Insider MVP and Windows & Devices for IT MVP. I'm here to help you with your problem.Did you lose your EFS certificate too?The Encrypting File System (EFS) is a built-in encryption tool for Windows. It is used to encrypt files and folders on your computer. You can reverse the encryption to access your files again.

How To Access Encrypted Files

To decrypt folders, follow the steps below:Right-click the folder or file, then click Properties.Click the General tab, then click Advanced.Uncheck the Encrypt contents to secure data checkbox.If you are decrypting folders, select the option Apply changes to this folder, subfolder and files.Click OK, then click OK again to exit the window.Let us know if the solution above works for you.Best regards, Andre Da Costa Independent Advisor for Directly. Open the Start menu, type 'certmgr.msc' in the 'Search programs and files' box and press 'Enter.' The Certificate Manager will open up.Confirm the operation or re-type your password, if prompted. Open the 'Personal' category in the left navigation pane, click on 'Certificates' and then click to select the certificate that says your account name under the 'Issued To' heading.Open the 'Action' menu, move your cursor over 'All Tasks' and click the 'Export' option.

Follow the prompts in the export wizard. Select the 'Yes, export the private key' and 'Personal Information Exchange' options when prompted, type a password for the certificateand click 'Finish' when done.Transfer the certificate file to the computer you want to open the encrypted file on and open the Certificate Manager on that computer. Open the 'Personal' category, open the 'Action' menu, move your cursor over 'All Tasks' and select the 'Import' option.Follow the prompts in the import wizard. Select the certificate file you transferred, type the certificate password, check the 'Mark this key as exportable' checkbox and select the 'Personal' category as the location for the certificate to be placed, when prompted.Click 'Finish' when done.

Double-click on the encrypted file to open it; the certificate you just transferred will grant you access to the file.Source:Best regards, Andre Da Costa Independent Advisor for Directly. Open the Start menu, type 'certmgr.msc' in the 'Search programs and files' box and press 'Enter.' The Certificate Manager will open up.Confirm the operation or re-type your password, if prompted.

Open the 'Personal' category in the left navigation pane, click on 'Certificates' and then click to select the certificate that says your account name under the 'Issued To' heading.Open the 'Action' menu, move your cursor over 'All Tasks' and click the 'Export' option. Follow the prompts in the export wizard.

Select the 'Yes, export the private key' and 'Personal Information Exchange' options when prompted, type a password for the certificateand click 'Finish' when done.Transfer the certificate file to the computer you want to open the encrypted file on and open the Certificate Manager on that computer. Open the 'Personal' category, open the 'Action' menu, move your cursor over 'All Tasks' and select the 'Import' option.Follow the prompts in the import wizard. Select the certificate file you transferred, type the certificate password, check the 'Mark this key as exportable' checkbox and select the 'Personal' category as the location for the certificate to be placed, when prompted.Click 'Finish' when done. Double-click on the encrypted file to open it; the certificate you just transferred will grant you access to the file.Source:Hello Andre,thanks for your help and time. This won't work because the old Windows 10 OS isn't running. I Just have a 1:1 copy of the C: Drive stored on my external HDD and the files which I need to be decrypted are lying there in my old Userfolder. I need to get thefiles decrypted on my new running Windows 10 OS (other direction).

Is this possible? Isn't there somewhere the key/certificate on my old C: Drive copy which I need to decrypt the file(s)? I thought I can just copy it and import and then thefile(s) get decrypted.