Try to load it up and select Browse for the folder and find the folder (in this case; Sachidanand Sankaranarayanan – The Lockdown Mandolin).
This is caused by the uploader saving the path to the folder on his own pc rather than wherever you have it installed.
Allow to load and then check it plays correctly.
Next click on the Load/Save icon in Kontakt and select Save as… from the drop down list and click on Instrument #1 (followed by the name).
This will bring up the Save as… dialogue box.
From the five choices at the bottom, select Patch only and leave the others empty.
Click on Save which will tell you it already exists and ask if you wish to replace it. This is the key as replacing it will then remember the path for the files and folder.
As long as you don’t rename the folders or files or change the relationship between the nki, folders and samples they should now load fine.