Under the Preferences tab all configuration settings and users preferences are defined. From this screen you can set how often the SMART status is checked, work modes, logging options and other. 
The Global notification settings for all drives are also located on this screen. You can configure common notification settings for all drives Active SMART detected. Please read below a detailed description for every preference or option.

Poll drives every N hours or minutes
Active SMART allows you to constantly monitor your disks for SMART events. You can set here how often the SMART status is checked. The time between status checks can be set up to a maximum of every 99 hours.

Enable monitoring at Windows startup
If you check this option Active SMART will be automatically loaded every time Windows starts. To show main Active SMART window double click on Active SMART icon in the system tray (near the system clock), or right click the icon and choose Show Active SMART.

Exit if no errors detected
If this box is checked Active SMART will check your drives only at startup. If Active SMART detect disk failure or changes in the disk SMART system, or critical drive temperature it will notify you or system administrator with various ways you defined for the drive where this event occur. If no problems detected and drive is OK then Active SMART finishes. This mode is useful if you reboot your PC every day, for example, so you can enable this mode and Active SMART will check your disks once a day - when Windows starts. If your drives are OK then Active SMART quits and will not use your system resources (however, Active SMART is specially optimized and almost don't use your system resources in the idle mode) 

Open Active SMART window at startup
When you enable this option the main Active SMART window will be opened every time the program starts. If this is disabled Active SMART will start minimized, and you can open it from the system tray menu or icon .

Log events
Enables or disables logging all SMART events and warnings to the text log file (you can view it in the Log tab). This file is a plain text file and located in the Active SMART folder (by default it's c:\Program Files\Active SMART\asmart.log)

Use system Event log
If this option is enabled all SMART events and warnings will also be logged to the Event log (only on Windows NT/2000 and XP).

Language
This is a list of all available language files for Active SMART user interface. These files located in Language folder. Look here if you want to create a language file for your own language.

Global notification settings for all drives section enables you to define a common (global) notification settings for all drive that Active SMART supports. To define custom settings for a certain drives use Drive Properties window.

Enable temperature warning 
Enable/disable notification about drive temperature changes and about critical drive temperature. Below this option you can set disk critical temperature. Active SMART will notify you if the drive temperature exceed this critical value.

Following options specify the default (common) notification method for all drives that don't use the custom notification settings. Active SMART will use this settings if it detect the SMART event or drive critical state, or drive overheating.

Popup message
Active SMART will show a popup message in case of any event.

E-mail message
In the remote messaging configuration, there is the ability to send Email notifications. This feature is extremely important to Administrators of remote systems or networks. In the event of a SMART alert or a drive exceeding the predetermined temperature, mail can be sent to a specified recipient so corrective action can be taken. To change Email settings press a button Email settings

Network message
Active SMART can send notification messages over the local network (like 'net send' command on Windows NT system.) This feature is very important to Administrators of networks. Message can be send to a specified recipient in the event of a SMART alert. To send a test message press button.

Play the sound
Plays the specified sound file (.wav) in case of SMART event of drive failure.
To browse the disk for sound file press 'Browse' button  
To play selected sound file press 'Play' button

Show disk status in the tray
If this option is enabled then the Active SMART tray icon will show the brief status of the last S.M.A.R.T. check. This tool tip will remain on the screen for 10 seconds. To hide it earlier just click on it.