Trialware or Trial Software, is
computer software that can be run for a limited period of time before it
expires and stops working. The idea behind this concept is that the user gets a
chance to try it out and then decide whether he or she would like to buy its
full version. It is actually a sample of original software that works for a
limited period of time. It may or may not have all the features of original
software. In either case, it ceases to work after its time-limit expires. This
article talks about how a trial version software works.
How does trial version software work
There are many methods that are used by
programmers to know when the trial period of a software has elapsed. In earlier
times, something as basic as checking the system date was done. But over
a period of time sophistication has entered. Since no two programmers
think alike all the time, there can be no certain method to be explained in
this context.
Some trialware makes entry into the Windows
registry about when it was installed, along with the time of installation. The
software, when launched, compares the registry noted date and time with
computer date and time. If the latter is greater, the trial version of the
software or trialware, as it is called, stops functioning. But this is the
easiest method that can be employed by any trialware. Such entries are not
created in obvious places under obvious names, but instead are ‘hidden’
Since programmers too know that it is easy to
scan registry with program remnants and reinstallation for use, they might add
few more hidden registry entries that do not look related to the trialware.
That means, when you install a trial version of a software, it may create a few
registry entries in say, HK_LOCAL_MACHINE or HK_CLASSES_ROOT where normally, no
user will look into. Further, the names of keys would be unrelated to the
program so that even if a user is figuring out keys to delete, he or she does
not know if a key belongs to the trial version of a software. That way,
programmers can prevent a working reinstallation of the trialware.
Trial software use hidden and system files
Some programmers create hidden files or system
files related to the trial version of a software and place it in System32
folder or into the folder containing drivers. They could even be 0 byte or
empty files. If they add an extension that goes .sys or .ini, users will think
twice before even editing the files. Junk cleaners too will ignore them.
Further, the files can be encrypted and if
users try to make any changes, the trial version completely stops working as
result of manipulation of the related files. In this case, when the program is
installed, it creates several files in different locations, especially the ones
that are related to Windows functioning. Based on the data written to these
files, the program can detect if the trial period is still remaining or if it
has expired. This is another explanation of how trial versions of software
work.
Trialware use Computer MAC address
In this case, the computers’ address is stored
to the servers of the software publishing company along with other details such
as data and time and probably a snapshot of the volume containing hidden files.
These hidden files have been explained in the above section. This storage of
MAC addresses of the computers or smartphones helps the trialware in deciding
two things. First, if the trial period has been expired. And secondly, it tells
the computing company that if the user is trying to install another version of
the trialware on the same machine.
For example, user can download the Student
Edition of Microsoft Office to a machine. The address of the machine is stored
to Microsoft’s server. After the trial period of 90 days, if the user attempts
to download and install another Student Edition of Microsoft Office to the same
machine, Microsoft knows it and prevents installations.
This method prevents a working reinstallation
of the trial version of a software, even if the user formats his Hard Disk
Drive. The MAC address of the computer or smartphone or tablet registered with
the publishers’ servers will tell the program that it was installed once on the
program. The drawback could be that if the user tries to reinstall the program
after a format even before the trialware’s trial period expired, she or he may
not be able to reinstall a working copy.
