Typically you can delegate permissions via the "Local Computer Policy" or
"Domain Computer Policy"
In the "Computer Configuration" / "Windows Settings" / "Security Settings" /
"Local Policies" / "User Rights Assignments"
However, I don't think you can delegate the right to run defrag
specifically.
I've heard people using a "Scheduled Task" to defrag once a month (running
as an administrator) - then they allow users to manually start this task
when needed.
--
MikeVa [MSFT]
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