Clock Guard Instruction Manual

Clock Guard is a software program for Windows 95/98/Me/2000/XP/NT computers that prevents the computer clock from being changed. That is, as long as Clock Guard is installed and active, you cannot change the time/date provided by the system clock. The clock will, of course, continue to run and update itself. There are various uses for Clock Guard. A few samples are:

1) Preventing files from being given falsified time/date stamps by manually resetting the system clock and then saving the file.

2) Prevent employees who are using a computer-based time clock from altering the time to allow themselves to "punch in" at a falsified time.

3) Prevent users who have time limited programs (programs that can only be used at certain times) from accessing these programs at improper times.

4) Prevent people who are paying for computer use on a time basis from resetting the clock to reduce the amount of time they pay for.

5) Prevent people who are restricted to a certain amount of computer time per day (usually children) from resetting the computer clock to give themselves more time.

Unlike other clock control programs, Clock Guard does not require an Internet connection. It does not automatically set the computer clock to the correct time by dialing up an atomic clock somewhere. It works by preventing sudden changes in the computer clock and by blocking access to the clock setting program.

Initializing Clock Guard

When you first run Clock Guard, it will ask you to set an administer password. The administrator password is required to temporarily disable Clock Guard if you want to reset the computer clock. It is also required to uninstall Clock Guard. Note: Passwords are case sensitive. This means, for example, that "Good" is not the same as "good" or "GOOD". Be sure to remember the EXACT password you select, including capitalization.

Once you select a password, program will ask you to select what types of protection you want. Review the description of the types of protection as explained on the screen or click on the Help button for additional information. Select the types of protection you want and then click on the Ok button. The main screen will then appear.

Registering Clock Guard

From the time you first run Clock Guard, you have a 30-day trial period to evaluate it. During that time, Clock Guard will be fully functional. If you decide you like Clock Guard, you should register and pay for it ($20). At the end of the trial period, if you do not pay for Clock Guard and input the registration code you receive, Clock Guard will be deactivated. That is, it will no longer prevent the computer clock from being reset. It will be reactivated when you input the registration code, which you will receive when you pay for Clock Guard.

There are several ways to pay for Clock Guard. The easiest way to register a single copy is to go to the site. From there, you can go to the payment page (links are in the third paragraph on the home page). Scroll down the page to the place where Clock Guard is listed. Input the serial number that appears on the registration screen for Clock Guard (the screen that asks you to register and input your registration code) and then click on the "PayPal buy now" button. You will be sent the registration code by email. You will normally receive this code within a day, although it may take a little longer under unusual circumstances (Internet problems, etc.).

You can also pay for Clock Guard by clicking on the Print button to print a form. You can then mail this form to the address given on the form or fax it to the fax number given on the form. You can pay by enclosing a check or by filling out the credit card information on the form. You can also pay by phone using your credit card. The number to call is 386-410-6769.

Volume discounts are available. Call 386-410-6769 or send an email to with information on how many copies you want to license for a price quote.

Main screen

The main screen has a pair or radio buttons (option buttons). Normally, the top option button is selected. This indicates that clock protection is on. If you click on the lower option button, Clock Guard will ask for the password. If you input the correct password, the bottom option button will be selected and clock protection will be deactivated. You can reactivate clock protection by clicking on the top option button again. No password is required to reactivate protection. If protection is properly turned on or off, you should see the word "Confirmed" appear next to the option you chose.

Note: The password is case sensitive. This means, for example, that "Good" is not the same as "good" or "GOOD". Be sure to use the EXACT password you selected when you set up the password, including capitalization. When inputting passwords, you can mask the password so that it cannot be read on the screen. You do this by clicking on the "Conceal password while typing" box to put a check in this box. When this box is checked, anything you type in the password box will be displayed as asterisks. The check box retains its last value, even if you exit the Clock Guard control panel or even reboot the computer.

In addition to the option buttons on the main screen, there are menus at the top of the window. These are explained below.


There are four options under the Files menu.

View Report: When Clock Guard performs an action, such as blocking the Windows Time Change program or resetting the clock, it saves a record of this. You can view a report of these actions with this option. There are two types of entry in this report. The first tells you that Clock Guard changed the time from one time to another. This means that Clock Guard detected a time change and changed the time back to the time it thought the correct time should be. The other report is that Clock Guard blocked an attempt to use the Windows time change program by closing the program window. You might want to view this report to see if anyone has been trying to tamper with the system clock. When you are finished viewing the list of actions that Clock Guard has taken, click on the Close button to close the report screen.

Clear Report: This option will clear all reported activity from the report. You might want to do this if the report is getting long and you want to start fresh.

Uninstall Clock Guard: If you select this option, Clock Guard will ask for the administrative password. If you provide the correct password, Clock Guard will be totally removed from your computer. You should only use this option if you have decided that you do not want to use Clock Guard ever again. This is the ONLY way to uninstall Clock Guard. Please do not try to uninstall Clock Guard by manually deleting files. Doing so will not only not uninstall Clock Guard, it will make it very hard to actually uninstall. Note: On some systems, especially some Vista computers, trying to uninstall Clock Guard by clicking on Files/Uninstall Clock Guard will generate an error and Clock Guard will not uninstall. If that happens, use the uninstall procedure in the Windows Control Panel by clicking on Settings under the Start button, then select Control Panel and then select Add/Remove Programs or Programs and Features and pick Clock Guard from the list of programs. Note: Exit the Clock Guard control panel before using this method.

Exit Clock Guard: This closes down the Clock Guard controller. Note: You cannot shut down the Clock Guard control panel while protection is turned off. If you try, the Clock Guard Controller will display a message box telling you that you must turn protection back on, and the Clock Guard Control screen will refuse to close. This is to protect you against turning off the protection and then forgetting to turn it back on before you close the control panel. If you want to get the Clock Guard control panel out of the way but still leave protection turned off, just minimize the control panel.


Under the Configure menu, there are two options. These are:

1) Set Protection Level - This lets you select the types of protection you want. Types of protection are:

Block Windows program for changing date and time - The most common way to change the computer time is to right click on the time displayed in the lower right corner of the screen, then click on "Adjust Time and Date". (The wording may vary slightly with different operating systems.) This will display the Windows program that allows you to set the time and date, as well as change the time zone and possibly a few other time related functions. The "Block Windows program for changing date and time" option causes Clock Guard to block this program from running. Without this program, most people cannot change the computer time or date.

Block DOS command prompt - Although only a small percentage of computer users know this, there is a way to change the system clock from DOS. Blocking the DOS command prompt prevents people from accessing your computer at the DOS level. For greater safety, it is best to activate this option, unless your users need access to the DOS command, which is very unlikely.

Block any sudden changes of time on this computer - Having Clock Guard block any sudden change of the time on this computer causes Clock Guard to actually reset the clock if it detects a sudden change of the computer clock. This protects against ANY change in the time. However, it can interfere with programs that set your clock, such as synchronizing with the server. Use of this option is not advised unless you believe that very sophisticated users have found another way to change your computer clock.

If you have Clock Guard reset the clock after time changes, you must set the maximum time change that Clock Guard should allow. Maximum time change is the maximum time that Clock Guard will allow the clock to change without resetting the clock. This allowed time change allows the computer to make small changes to synchronize with the server or calibrate with the Internet if the clock gets a little off. The recommended time is 30 seconds, but you can make it longer if Clock Guard is interfering with clock synchronization. The minimum allowed is 15 seconds.

Set the level of protection you want, and then click on the Ok button. This level of protection will remain in effect until you change it. This is not like the Clock Guard Protection On/Off switch on the main control screen, which resets to On as soon as you exit the program or turn off the computer.

2) Set password - If you select this option under the Configure menu, Clock Guard will ask you for the current password. When you input the current password, it will ask you to select a new password. Type the new password and click on the OK button. You can cancel changing the password by clicking on the Cancel button.


If you have not yet registered Clock Guard, this option will appear on the top of the window. Clicking on it will display the registration screen, which also appears when you first run Clock Guard until it is registered.

Uninstalling Clock Guard

There are two ways to uninstall Clock Guard. The preferred method is to click on Files and then Uninstall Clock Guard on the Clock Guard control panel. If this generates an error message, the alternative is to use the uninstall procedure in the Windows Control Panel by clicking on Settings under the Start button, then select Control Panel and then select Add/Remove Programs or Programs and Features and pick Clock Guard from the list of programs. Note: Exit the Clock Guard control panel before using this method.

Bug reports, help requests, suggestions

If you need help with this program, have found a bug, or have a request for additional feature, please contact Leithauser Research. The best way is to send an email to You can also call Leithauser Research at 386-410-6769 .

If you are suggesting an additional feature or other improvement, we will make these changes and release a new version soon if we believe these improvements would have broad appeal. You will be notified when the new version is released. If we feel that the changes you suggest are not commercially viable, we can still create a custom version of Clock Guard for you for a fee. Contact Leithauser Research if you are interested in this.

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