I have lost my serial number for Lightroom 4 program. How can I obtain it?
You can check your Adobe account and see if it's listed there.
Links that may help-
Find your serial number quickly
Preference and other file locations in Lightroom 5
Or if you have LR4 installed in Windows.
C:\ProgramData\Adobe\Lightroom\Lightroom 4.0 Registration.lrreg
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