AxCrypt is a free, open source file encryption program that allows you to quickly and easily encrypt and decrypt files and folders in Windows. It integrates into Windows Explorer allowing you to use the context menu to encrypt and decrypt individual files and folders.
This two-part series of posts shows you how to use AxCrypt to encrypt and decrypt files, create self-decrypting files, create a copy of the portable AxDecrypt program, permanently delete files by shredding them, and assign random filenames to encrypted files.
Download AxCrypt from
http://www.axantum.com/AxCrypt/Downloads.html.
AxCrypt runs on 32-bit and 64-bit Windows 2000/2003/XP/Vista/2008/7. Be sure you download the correct version.
Install AxCrypt
To install AxCrypt, double-click the .msi file you downloaded.
The AxCrypt Setup Welcome screen displays. Click Next.
Read through the End-User License Agreement and select the I accept the terms in the License Agreement check box. Click Next.
The Custom Setup screen displays. Click Next to continue.
If you change any options on the Custom Setup screen and want to return to the defaults, click the Reset button.
NOTE: If you want to see how much space you have available and how much AxCrypt will use. Click the Disk Usage button on the Custom Setup screen to view the Disk Space Requirements screen. Click OK to return to the Custom Setup screen.
On the Ready to install screen, click Install.
Click Finish on the Completed screen to close the setup wizard.
If you want to receive notifications of updates to AxCrypt, enter your email on the dialog box that displays and click OK.
Create a Key File
AxCrypt does not work by starting a separate program, instead it’s fully integrated into the Windows Explorer. Use AxCrypt to encrypt and decrypt files and folders by selecting one or more files or folders that you’d like to operate on. Some operations are not applied to specific files or folders, but you still need to right-click something to bring up the AxCrypt menu.
AxCrypt can use a key file along with the passphrase when encrypting files and folders. A short text file long enough to really use the full strength of the encryption algorithm is generated. This provides extra security. If you generate and use a key file when encrypting files and folders, be sure to keep the key file secret. You should store it on a USB flash drive or other removable storage separate from your encrypted files.
NOTE: DO NOT encrypt the key file with itself! If you do, all data encrypted with that key file is lost, unless you have a backup of the key file. It is always recommended to print the key file on paper and store that paper in a safe place. That way you can recreate the key file, if needed.
Before using a key file to encrypt a file, you must create one. To do this, right-click on any file and select AxCrypt | Make Key-File from the popup menu.
NOTE: It does not matter which file you right-click on because the Make Key-File option is not specific for a file.
A warning dialog box displays information about creating a key file. If you don’t want to see this dialog box every time you create a key file, select the Don’t show this message again check box. Click OK to continue.
Select a USB flash drive to store the key file. A default name is provided in the File name edit box. Click Save.
Encrypt a File
To encrypt a file, right-click on the file you want to encrypt and select AxCrypt | Encrypt from the popup menu.
NOTE: The Encrypt option replaces the original file with the encrypted file. If you want to preserve the original non-encrypted file, select the Encrypt a copy option.
On the AxCrypt dialog box, enter your passphrase in the Enter passphrase edit box and again in the Verify passphrase edit box. Click the … button in the Key-File box.
A warning dialog box displays confirming that you want to use a key file to encrypt your file. Remember to keep your key file secret and safe. Click OK to continue.
Navigate to the USB flash drive where you saved your key file. Select the file and click Open.
AxCrypt can remember any number of passphrases for quick decryption and a default passphrase to use when encrypting files. AxCrypt maintains an in-memory cache of used passphrases – one to be used by default for encryption, and as many as you like to be tried for decryption before prompting you for a passphrase. This cache is cleared every time log out of your account or reboot your computer.
This feature makes the usage of AxCrypt much more convenient, and saves you from the trouble of re-entering your passphrase every time you decrypt a file. However, if you use this feature, be sure you apply a password to your screensaver or take other precautions so no one else can access your encrypted files automatically while you are away from your computer.
If you want AxCrypt to remember the passphrase you entered for the file you are encrypting, select the Remember this for decryption check box.
To use the passphrase you chose for the current file being encrypted as a default passphrase to encrypt other files, select the Use as default for encryption check box.
Click OK on the AxCrypt dialog box to encrypt the file.
If the passphrases you entered into the two edit boxes don’t match a dialog box warning displays. Click OK to return to the AxCrypt dialog box and enter your passphrase correctly in both edit boxes.
If you select a key file you attempted to create yourself instead of one created using AxCrypt, a dialog box displays warning you that data loss might occur if you don’t use a standard key file. If you don’t want to see this message again, select the Don’t show this message again check box. Click OK to return to the AxCrypt dialog box. Cancel your encryption process and create a standard key file using AxCrypt as mentioned earlier in this post. Then, encrypt your file again.
Once you have successfully encrypted your file, you will see a .axx file in the folder in place of the original file, if you used the Encrypt option.
NOTE: When you select a folder to encrypt, all the files within that folder are encrypted separately, using the same passphrase and key file, and will have the .axx extension. You can work with each of the encrypted files in that folder separately.
Decrypt and Edit an Encrypted File
To edit an encrypted file, you can double-click the file just like you would normally. If you decrypt a file by double-clicking on it, the file automatically opens with the associated program and you can edit it, save it, and close it and it will remain encrypted once closed.
To decrypt the file and convert it back to an unencrypted file (the encrypted file is not preserved), right-click on the .axx file and select AxCrypt | Decrypt from the popup menu.
On the dialog box that displays, enter the passphrase you used to encrypt the file. If you used a key file to encrypt the file, click the … button in the Key-File box.
On the Open dialog box, navigate to the USB flash drive where you saved your key file, select the file and click Open.
Click OK to decrypt the file. If you selected the Decrypt option to decrypt the file, the original file is written to the same directory and the encrypted file no longer exists. You can simply double-click the file to open it in its associated program. If you double-clicked on the encrypted file to decrypt it, the file automatically opens in the default associated program.
Wrap Up
This was the first post in a two-part series about using AxCrypt to easily and quickly encrypt and decrypt files and folders.
In this post, we covered installing AxCrypt and using it to encrypt and decrypt files through the context menu in Windows Explorer.
Stay tuned for the next post where we will cover creating self-decrypting files, creating a copy of the portable AxDecrypt program, permanently deleting files by shredding them, and assigning random filenames to encrypted files.
by Lori Kaufman