PST Password Security

Rollins Duke   
Published: May 13th, 2024 • 4 Min Read

MS Outlook Password Security

While forming a fresh Personal Storage Table (PST) file in Microsoft Outlook, a user can easily encrypt it using a password with 3 different options of encryption. The user can encrypt a PST file in Outlook optionally while creating it.

Encryption Security Settings for Outlook PST Files

In MS Office Outlook email client version 2003, on creating a fresh data file, which is also called as the Personal Stores PST file with filename extension as .pst, an option is available to choose one particular encryption level. The options for encryption available are 1) No Encryption, 2) Compressible Encryption (this is the default one), and 3) High Encryption. The user can choose from these 3 different encryption or password protection options to encode the data and information stores in the Outlook data PST file. Once done, this setting cannot be changed after PST file creation. Encryption will encode that PST file and therefore after the encryption, the contents of the file will not be read by any other programs. On selecting compressible or high encryption (this is the best encryption), and setting the PST file password, the PST file will be secured with that particular password. Later on, on trying to open/load that specific PST file with MS Outlook program, the application will prompt the user to enter the password to open the file. Both, Compressible as well as High Encryption options give only basic protection or security. Compressible Encryption option is the default security setting in Outlook. The user must use Compressible Encryption in case where the disk space has more importance than the protection of data. However, in case security is of prime concern to the user and is more important than the disk space, then the user must use High Encryption, and after choosing that option, he must select a specific password for the PST file.

The Three PST Encryption Options

  • No Encryption – This encryption means that the user has not encrypted the file. This particular option will not encode the PST file. User will be able to read that PST file using a hexadecimal editor or a text editor.
  • Compressible Encryption – This encryption setting is set by default. Choosing this option will encode the PST file in a particular format allowing compression, however, that PST file will be compressed only when the user has a compression program available on his system. In this option, the user cannot read that specific PST file using a text editor program or a hexadecimal editors. This type of encryption encodes the PST file data in a way that other users cannot read the mail messages with text editors or hexadecimal editor programs. Only professional hackers will be able to beat this security using very special tools. This compressible encryption also allows PST file compression with various compression tools such as PKZIP utility or other built-in ones that are available on various MS Windows file systems.
  • High Encryption – This is somehow the best encryption. This type of security setting or password protection has the highest level of security. Choosing this encryption option will encode the Outlook PST file of the user in a specific format which provides very high protection. If the user has a program for disk-compression available on his machine, then that specific PST file will be compressed, however, to a lower degree than it is there choosing the option of Compressible Encryption. The PST file encrypted with this option of high encryption will not be read using text editors or hexadecimal editors. This type of encryption level makes use of stronger encryption form which is very difficult to even hack by professional hackers. It is also very time-consuming for the Outlook program to read & write.