Mario, each license key has its own term during which it is valid.
This term is embedded in the key at the time it is generated. The terms of different keys cannot be added together: https://www.kerish.org/en-us/order_faq.php#faq_5

Please supply link for multiple machines. I have looked and unable to find.

Thanks.

PETE ADAMS,
Read my comments AGAIN.
that is not what I said

IrishMaster,
I copied the things below from the home page. You are saying this is not enough information?!!
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Kerish PC Doctor is a complete care solution for computer maintenance that utilizes the most promising developments in this area.

Due to its unique system, Kerish PC Doctor prevents Windows crashes in real time and also safely fixes invalid entries of the system registry.

The application regularly performs a maximally thorough and safe cleaning of your system to eliminate accumulated digital "trash", thereby increasing the efficiency of your computer in the best way possible.

Kerish PC Doctor protects your PC against malware and potential vulnerabilities and monitors computer settings that are important from the point of view of security.

The Smart Update system promptly updates the application's databases, which are constantly being improved by our experts. Thanks to this system, the software suite is becoming more effective every day, making our solution the most promising in its class.


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Key Features Technologies Advantages Awards Download
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Key Features
Repair: Cleaning: Optimization: Protection:
* Prevent Windows failures in real-time * Clean digital "trash" * Improve game performance * Malware protection
* Fix invalid registry entries * Delete outdated application cache * Optimize Windows settings and system services * Eliminate vulnerabilities in Windows and installed software
* Monitor computer temperature * Purge invalid items and shortcuts * Optimize Internet connection speed * Monitor key PC events

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— Monitor your computer’s health

Due to its unique and unparalleled Real-Time Failure Detection technology, Kerish PC Doctor can prevent Windows crashes in real time. The program regularly corrects invalid entries in the system registry. In addition, Kerish PC Doctor has the most comprehensive database of solutions to the most common Windows problems that can be applied with just one click. Just select the desired solution from the list.
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Clear away digital "trash"

Kerish PC Doctor regularly cleans your computer of accumulated digital "trash", including system and software cache files. Our most advanced cleaning method, Intelligent PC Clean, factors in the date when each file was last accessed. This prevents the accidental deletion of any temporary system or software files that are still needed. Unlike other products, this method ensures the most accurate and safe cleaning of files. —
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— Improve performance

Kerish PC Doctor will analyze your system and make recommendations to improve your computer's performance that can then be applied with a single click. The program makes it possible to optimize your operating system configuration, the operation of system services, and internet connection settings in order to achieve maximum performance. Game Booster technology also helps you increase game performance.
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Protect against threats and vulnerabilities

Kerish PC Doctor protects your computer against malicious and potentially unwanted programs and also secures vulnerable Windows settings.
In addition, the program also provides timely warnings when new vulnerabilities are reported in installed software and will help you update this software. The Kerish Deblocker function effectively combats malicious software blocking your computer even if it is already blocked. —
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— Take complete control

Kerish PC Doctor helps you maintain control over the most significant actions that take place on your computer.
The program can prevent the appearance of new programs in the startup folder (programs that run when Windows boots), the installation of the new system services, changes to the start-up pages of web browsers, the installation of new extensions to web browsers, and many other things.
You can block these actions with just one click.

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Advantages
* Operates in real time without user intervention
The software works according to the principle "install it and forget it", providing high-quality maintenance for your computer in real time, 24 hours a day, 7 days a week, with no need for user intervention. Of course, the software can also be run manually.

* Impeccable reliability and safety
Kerish PC Doctor uses the most advanced and intelligent diagnostic algorithms.
Unlike the majority of other programs in its class that try to find as many "errors" as possible, Kerish PC Doctor will not harm the system.

* Unique failure detection and cleaning technologies
Kerish PC Doctor includes a variety of unique technologies that cannot be found in any competing software.
This makes Kerish PC Doctor the most promising solution in its class.

* Regularly-occurring core and algorithm updates
Our experts are constantly improving the program.
Kerish PC Doctor can update the error-correction and cleaning algorithms that is uses to clean your computer of digital "trash" every time you connect to the Internet.

* Full set of tools for working with Windows
The application provides a complete set of tools needed by advanced users to work with the operating system.
In just a few clicks you can start working with startup items, installed software, system services, recovery points, and other operations.

* Modern, user-friendly interface
Kerish PC Doctor has an attractive, user-friendly interface.
Both beginners and experienced users will be able to use the program with ease.

Bruce Fraser, I am talking about GAOTD home page.

IrishMaster,
With every GAOTD giveaway, the bar on the right gives links with the name of the company, and their website with all the information a person needs. It's right there, just one click away.