The information provided here can be used to troubleshoot system related problems.
It can't be used for solving encryption -related issues (like when you encrypt html source code of a file and then it does not work as expected, image protection problems etc. )

In some very rare cases you may experience problems such as Windows generated error messages like
   - 'the program has encountered a problem and needs to close. We are sorry for the inconvenience.'
   - 'the program has performed an illegal operation....'
or similar, or HTML Guardian may just unexpectedly quit with no apparent reason.

There are two main causes for such problems - a misconfigured/corrupt parts of the operating system, or a software conflict with another application or service which attempts to interact with HTML Guardian in an improper way.
Following the steps below will solve the problem in 99% of the cases. After each step check if the problem is solved, if not proceed with the next one.

1. Make sure you have the most recent version.

Click Help/About to check which version you have installed, and visit protware.com to check which is the latest available version. If you don't have the latest version:
   - users of the free Personal edition - download and install the latest version available. There is no need to uninstall the current version, just run the latest installer and it will update the program.
   - registered users of the Professional / Enterprise edition - click the 'Update' menu -> 'Check for updates'
   - users with volume licenses (corporate or educational) - click the 'Update' menu and select one of the available menu items - 'Check for updates <server name>'. Note that if the program is installed in a managed mode, you may not be allowed to update it - in such case contact the appropriate person for assistance (see Help -> Permissions).

2. Disable the so called 'Data execution prevention' (DEP)
(applies only to Windows XP service pack 2 and later operating systems. Skip this step if you use Windows 95, 98, ME, NT4, 2000, or XP without service pack 2)

Open the Control Panel. Double click 'System'. Click the 'Advanced' tab.
Under 'Performance', click the 'Settings' button. Click the 'Data Execution Prevention' tab.
There are two options available - the default and strongly recommended option is 'Turn on DEP for essential Windows programs and services only' - if not already selected, select it. If for some reason you want to keep the other option ('Turn on DEP for all programs and services except those I select'), then add HTML Guardian to the exclusions list - to do so click the 'Add' button, navigate to program's installation folder and select all the executable files (with .exe extension) inside it.
Changes in DEP settings become effective after a reboot.
Note: some new computers have such an option in their BIOS. Check your BIOS and disable DEP there first, and then in Windows, as described above. In some BIOSes it may be named 'NoExecute Bit' or 'NX bit', but it's the same thing.

3. (Re)install Windows scripting runtimes

This is a very important part of the Windows operating system that often gets corrupt by improperly written third party software you may have installed.
Download the latest official Microsoft distribution of Windows scripting runtimes from here and install the version that is suitable for your OS (see the Readme.txt file).

4. Reinstall HTML Guardian

Reboot your computer.
Run HTML Guardian's installer immediately after the system starts, before starting any other application.

5. Reconfigure, and then stop, all potentially problematic applications

Potentially problematic applications are these that try to check, modify or otherwise interact with other programs. Often, these activities may result in locked files, memory corruption and other problems that may lead to an unexpected behavior or crashes. Common sources of such problems are:
   - virus scanners
   - security related programs, like firewalls
   - anti-spam programs
   - ad-blocking programs
   - programs that 'customize' Windows, put 'skins' on other programs etc.

Most of the programs mentioned above have an option to exclude certain files/folders from permanent (real-time) monitoring. It is strongly recommended to configure all of them to exclude HTML Guardian's installation folder from their activities (from time to time you may perform an on-demand check of the installation folder to be sure it does not contain any threads).
If reconfiguring does not help, or can't be done, stop these applications and check if the problem remains. It is recommended to reconfigure/stop them one by one and check if the problem is fixed. If you find a conflicting application, restore the previous settings of all the others.

6. In case none of the above helps

If the problem still remains, press CTRL+ALT+DEL keys to invoke Windows Task Manager. Click the 'Processes' tab. Start to terminate the processes one by one (to do this right click a process and select 'End process tree'), after each check if the problem is solved.