If your organization acquires a QlikView Server license (Small Business or Enterprise), to license QlikView Personal Edition, you are leasing a license for a QlikView Server and to keep the lease, the desktop application has to contact the server every 30 days.
License Key and LEF:
These two methods are used to apply a Local Client License, I understand that this type of license is already discontinued. The difference between both methods, the first one works when it is possible to contact the Qlik license server online, and validate the license. The second method works when you do not have access to the internet to validate your license code.
Regular users connect to the server using one of the available clients. Each use needs a license of some kind, either named CAL, or a Document CAL, or a session CAL, or a Usage CAL. All these licenses can be contained with the QlikView Server license. Server is used to open, process and serve the documents to the clients by Access Point.
Only the Named CAL license allows the license leasing to QlikView Desktop. Each Named CAL is assigned to a single user.If your need is to license 10 QlikView Pesonal Edition, your QlikView server license needs 10 Named CAL.
I recommend you read about the QlikView licensing in the Help, and call a sales representative in your city,
Re: Difference between applying QlikView license key vs leasing QlikView license
Most information has already been provided to you, but I think this question needs another answer:
"2. Change the Personal Edition to licensed version.
For this scenario, which approach would be the best? Leasing license or License Key entry?"
A license key is only valid for a specific product. So you can have a license key for a QlikView desktop client, or for a QlikView server, or for a Publisher, etc.. etc.. What type of product it is valid for is governed by the LEF.
So when you want to license your QlikView Desktop client, it is up to what sort of license you own. If you own a QlikView developer license that you have not yet used, then that can be applied to the Desktop client. If you own a QlikView server license with Named User CALs (!), then you can license a QlikView server and then lease a license to the Desktop client using a Named user CAL. But you cannot use that LEF or license key from the QVS directly to apply it to the Desktop client.
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