Hi,
Thanks for using the HP Support Community.
In order to use the Scan to computer, the HP FULL software solution needs to be installed first.
After installation, enable the Scan to Computer on the software.
Download and install the software from this link:
https://support.hp.com/sg-en/drivers/selfservice/swdetails/hp-officejet-4650-all-in-one-printer-seri...
These resources will be useful:
How to Scan to Computer
How to use "Scan to Computer" properly
This resource will show how to create a Scan shortcut on the desktop:
Hope that helps.

I am an HP Employee
Although I am speaking for myself and not for HP.
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