Windows maintains a list of programs that have been executed on the operating system in the Windows Registry. The Windows program history contains detailed information about the programs that have been launched by the active Windows user.
The feature has been available for a long time, and Microsoft has continued to use it on all modern versions of the Windows operating system including Windows 7 and newer versions.
The information is stored in the Windows Registry under a UserAssist key which contains various information that are encrypted using the ROT-13 algorithm.
The information stored under the UserAssist key in the Registry can become a privacy and security risk if someone manages to get local access to the computer or remote access to the Registry. Also, you may use them to find out if another user who had access to a PC launched programs in your absence.
The program history is stored under the following Registry key:
HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionExplorerUserAssist
Several applications have been created to automatically decrypt the information and display them in a readable form to the user.
UserassistView
One of those programs is UserassistView by Nirsoft.
The portable software program displays a list of item names, their index number, times they were started, the modified time and ClassID.
You can sort the information with a click on a column header, for instance by time, item name or times the file has been opened on the system.
It is possible to delete select entries or all entries from the listing using the application.
You may run the program from the command line. This allows you to export the data to one of the supported document formats, e.g. csv or XML.
The UserAssist key will however be automatically filled with new information from that point on so that it might be a better idea to schedule a regular cleaning job with a program like CCleaner.
The program history can also be saved as text, csv or html files for further inspection. UserAssistView is compatible with all Windows NT based operating systems including Windows 7. It can be downloaded directly from the Nirsoft homepage.
The program can be quite useful, not only because it enables you to remove select entries from the Windows Registry but also as an option to verify that a cleaning program did remove the information from the Windows system.