Follow the Xampp installation steps in below link.
https://linuxkbv.blogspot.com/2018/07/xampp-installation-on-centosrheloel7.html
Download OrangeHRM setup from below link.
https://excellmedia.dl.sourceforge.net/project/orangehrm/stable/4.1/orangehrm-4.1.zip
Extract and copy the folder into Xampp htdocs folder.
/opt/lampp/htdocs
Start the Apache and MySQL services in Xampp.
Now hit http://localhost/orangehrm-4.1 in browser and installations will come.
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Select the next step.
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Accept the License and proceed forward.
Choose default values are change as per your requirements.
Following steps are for manually creation of Database.
CREATE DATABASE orangehrm;
Create a database user called orangehrmuser with new password
CREATE USER 'orangehrm'@'localhost' IDENTIFIED BY 'Password';
Then grant the user full access to the database.
GRANT ALL ON orangehrm.* TO 'orangehrm'@'localhost' IDENTIFIED BY 'Password' WITH GRANT OPTION;
Finally, save your changes and exit.
FLUSH PRIVILEGES;
EXIT;
Select Next and you may face the disabled status.
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Enable MySQL Event Scheduler status.
Edit this file and add following line.
/opt/lamp/etc/my.cnf
event_scheduler=ON
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Save the file and Re- check then Next.
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Enter the Admin User Creation and Next.
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Check the configuration details and Proceed to Install.
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Installation complete. Now login and configure internal configuration
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Documentations Links:
https://www.orangehrm.com/assets/Documents/User-Guides/OrangeHRM-OS-3.3-Administrative-User-Guide.pdf
https://www.orangehrm.com/resources/download/orangehrm-user-guides/
https://www.orangehrm.com/assets/Documents/User-Guides/OrangeHRM-OS-3.3-Supervisor-User-Guide.pdf
https://www.orangehrm.com/assets/Documents/User-Guides/OrangeHRM-OS-3.3-ESS-User-Guide.pdf