A crack is a copyright infringement. In our earlier article, we have explained type of cracks and application protection methods. To make a crack, crackers mainly use disassemblers, debuggers, and hex editors. Nothing new is programmed, but only how the original code works in order to change the program in a targeted manner.
Many programs commercial on the Internet have a trial period (usually 30 days) and then require registration (purchase) in order to continue working. Trial reset involves modifying and/or deleting registry keys and/or files containing information about the trial period. Crackers develop “trial resetters” for specific programs or sometimes for a group of programs from the same manufacturer, which do this with the click of a mouse. For some older programs, it was sufficient to change the date and time of the computer to the beginning of the trial period if you wanted to work with them. Some programs can also simulate a “virtual date” and a “virtual time.” Some programs can only be used a few times during the trial period and then refuse service until registration. (In the registry key and/or the hidden file, the number of program starts is recorded; this is requested at the start of the program, and when the specified number is reached, the program can only be used after registration. Here, simulating a wrong date and time is pointless.)
Many programs leave a hidden value in the registry when they uninstall, the presence of which is queried during the first installation (its absence here means that the trial period has not yet started) and during a new installation, so it is not possible to reset the trial period by simply uninstalling and reinstalling. Another method for a trial reset is a virtual machine. Here, a complete PC with installed software is emulated and runs as an application in a Windows window. The condition of the machine can be frozen and reset again and again. In this way, the system can also be reset to the day before the installation of the demo version at any time. However, the virtual system does not have the performance of the PC, and computationally or graphics-intensive applications run more slowly. Sometimes it is recommended to make a copy of the entire registry before installing the program. At the end of the trial period, you can then reset the registry to its pre-installation state. However, any changes made in the meantime by other programs or the operating system will also be lost, and any hidden files containing information about the trial period will remain unchanged. The most effective, but extreme, way to get a new trial period is to reformat the system hard drive, which erases all of its contents, including registry entries and hidden files (the operating system needs to be reinstalled and the computer has to be set up again).
One method to make trial resets pointless is to limit the program during the trial period (certain features are only available in the registered version, created graphics, videos and printouts are watermarked, the program runs only 10 – 20 minutes and then automatically shuts down, etc.). Some programs need to be activated on the Internet for the trial period and connect to the Internet at startup to check if the trial period has expired. This means that the information about the probationary period is not stored on the user’s computer, but on an external Internet server, making manipulation extremely difficult. The most likely option would be to remove this query in the program code. The disadvantages of this procedure are that you cannot use the program without an Internet connection, even if it does not require Internet access anymore (the server for data retrieval could also be temporarily unavailable or completely switched off), and that you have to register in advance (data protection!), even if you no longer use the program after the trial period has ended. but wants to uninstall.
Some programs have an unlimited trial period, but are restricted as long as they are not registered.
Some programs, which can be converted from a free to a full version by registering, do not start their trial period on the day of installation, but let the user decide for himself when or if he wants to test the additional functions at all. In the meantime, the user only has access to the features of the free version. An example of such a program is Malwarebytes.
For some programs, especially those that are frequently updated, such as antivirus and other security software, you only purchase a time-limited license (often for 1-3 years) when you register, which must be renewed for a fee after it expires. (In some cases, the program no longer works at all or only to a limited extent after the license expires, in others it continues to work but can no longer be updated.) Some programs require you to purchase multiple licenses if you want to use all the features.